Document and Entity Information - USD ($) $ in Billions	12 Months Ended
Document and Entity Information - USD ($) $ in Billions	Dec. 31, 2018	Feb. 14, 2019	Jun. 30, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Nasdaq, Inc.
Entity Central Index Key	0001120193
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Trading Symbol	ndaq
Amendment Flag	false
Entity Common Stock, Shares Outstanding		165,420,039
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 10.5
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 545	$ 377
Restricted cash	41	22
Financial investments, at fair value	268	235
Receivables, net	384	356
Default funds and margin deposits	4,742	3,988
Other current assets	390	532
Total current assets	6,370	5,510
Property and equipment, net	376	400
Goodwill	6,363	6,586
Intangible assets, net	2,300	2,468
Other non-current assets	291	390
Total assets	15,700	15,354
Current liabilities:
Accounts payable and accrued expenses	198	177
Section 31 fees payable to SEC	109	128
Accrued personnel costs	199	170
Deferred revenue	194	161
Other current liabilities	253	130
Default funds and margin deposits	4,742	3,988
Short-term debt	875	480
Total current liabilities	6,570	5,234
Long-term debt	2,956	3,727
Deferred tax liabilities, net	501	225
Non-current deferred revenue	87	126
Other non-current liabilities	137	162
Total liabilities	10,251	9,474
Commitments and contingencies
Nasdaq stockholders’ equity:
Common stock, $0.01 par value, 300,000,000 shares authorized, shares issued: 170,709,425 at December 31, 2018 and 172,373,432 at December 31, 2017; shares outstanding: 165,165,104 at December 31, 2018 and 167,441,030 at December 31, 2017	2	2
Additional paid-in capital	2,716	3,024
Common stock in treasury, at cost: 5,544,321 shares at December 31, 2018 and 4,932,402 shares at December 31, 2017	(297)	(247)
Accumulated other comprehensive loss	(1,530)	(862)
Retained earnings	4,558	3,963
Total Nasdaq stockholders’ equity	5,449	5,880
Total liabilities and equity	$ 15,700	$ 15,354

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	170,709,425	172,373,432
Common stock, shares outstanding (in shares)	165,165,104	167,441,030
Common stock in treasury (in shares)	5,544,321	4,932,402

Consolidated Statements of Income - USD ($) $ in Millions	12 Months Ended
Consolidated Statements of Income - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues:
Total revenues	$ 4,277	$ 3,948	$ 3,704
Transaction-based expenses:
Transaction rebates	(1,344)	(1,158)	(1,092)
Brokerage, clearance and exchange fees	(407)	(379)	(336)
Revenues less transaction-based expenses	2,526	2,411	2,276
Operating expenses:
Compensation and benefits	712	670	665
Professional and contract services	144	153	153
Computer operations and data communications	127	125	111
Occupancy	95	94	86
General, administrative and other	120	82	73
Marketing and advertising	37	31	30
Depreciation and amortization	210	188	170
Regulatory	32	33	35
Merger and strategic initiatives	21	44	76
Restructuring charges	0	0	41
Total operating expenses	1,498	1,420	1,440
Operating income	1,028	991	836
Interest income	10	7	5
Interest expense	(150)	(143)	(135)
Gain on sale of investment security	118	0	0
Net gain on divestiture of businesses	33	0	0
Asset impairment charge	0	0	(578)
Other investment income	7	2	3
Net income from unconsolidated investees	18	15	2
Income before income taxes	1,064	872	133
Income tax provision	606	143	27
Net income attributable to Nasdaq	$ 458	$ 729	$ 106
Per share information:
Basic earnings per share (in dollars per share)	$ 2.77	$ 4.38	$ 0.64
Diluted earnings per share (in dollars per share)	2.73	4.30	0.63
Cash dividends declared per common share (in dollars per share)	$ 1.7	$ 1.46	$ 1.21
Market Services
Revenues:
Total revenues	$ 2,709	$ 2,418	$ 2,255
Corporate Services
Revenues:
Total revenues	528	501	477
Information Services
Revenues:
Total revenues	714	588	540
Market Technology
Revenues:
Total revenues	270	247	241
Other revenues
Revenues:
Total revenues	56	194	191
Transaction-based expenses:
Revenues less transaction-based expenses	$ 56	$ 194	$ 191

Consolidated Statements of Comprehensive Income (Loss) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2018

Dec. 31, 2017

Dec. 31, 2016

Net income attributable to Nasdaq

$ 458

$ 729

$ 106

Other comprehensive income (loss):

Foreign currency translation gains (losses)

(240)

214

(183)

Income tax benefit (expense)

(11)

(96)

Foreign currency translation, net

(251)

118

(115)

Employee benefit plan adjustment gains (losses)

(2)

Employee benefit plan income tax (benefit) expense

(9)

Employee benefit plan, net

(1)

Total other comprehensive income (loss), net of tax

^[1]

(251)

117

(115)

Comprehensive income (loss) attributable to Nasdaq

207

$ 846

$ (9)

Accumulated Other Comprehensive Loss | Accounting Standards Update 2018-02

Reclassification from AOCI, tax amount

$ (417)

[1]	(1) Excludes a reclassification impact of Tax Reform of $417 million. See “Tax Cuts and Jobs Act,” of Note 17, “Income Taxes,” for further discussion.

Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Total	Common stock	Additional Paid-in Capital	Common Stock In Treasury, at Cost	Accumulated Other Comprehensive Loss	Retained Earnings
Common stock, shares outstanding (in shares) at Dec. 31, 2015		164,324,270
Balance at Dec. 31, 2015	$ 5,609	$ 2	$ 3,011	$ (111)	$ (864)	$ 3,571
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	106					106
Other comprehensive (loss) income	(115)				(115)
Cash dividends declared per common share	(200)					(200)
Share repurchase program (in shares)		(1,547,778)
Share repurchase program	(100)		(100)
Share-based compensation (in shares)		2,361,699
Share-based compensation	$ 86		86
Stock option exercises, net (in shares)	1,219,820	1,219,820
Stock option exercises, net	$ 41		41
Other issuances of common stock, net (in shares)		(770,790)
Other issuances of common stock, net	1		66	(65)
Issuance of Nasdaq common stock related to a prior acquisition (in shares)		992,247
Common stock, shares outstanding (in shares) at Dec. 31, 2016		166,579,468
Balance at Dec. 31, 2016	5,428	$ 2	3,104	(176)	(979)	3,477
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	729					729
Other comprehensive (loss) income	117				117
Cash dividends declared per common share	$ (243)					(243)
Share repurchase program (in shares)	(2,843,519)	(2,843,519)
Share repurchase program	$ (203)		(203)
Share-based compensation (in shares)		2,384,821
Share-based compensation	$ 70		70
Stock option exercises, net (in shares)	1,102,830	1,102,830
Stock option exercises, net	$ 24		24
Other issuances of common stock, net (in shares)		(774,817)
Other issuances of common stock, net	(42)		29	(71)
Issuance of Nasdaq common stock related to a prior acquisition (in shares)		992,247
Common stock, shares outstanding (in shares) at Dec. 31, 2017		167,441,030
Balance at Dec. 31, 2017	5,880	$ 2	3,024	(247)	(862)	3,963
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	458					458
Other comprehensive (loss) income	(251)				(251)
Reclassification impact of Tax Reform	0				(417)	417
Cash dividends declared per common share	$ (280)					(280)
Share repurchase program (in shares)	(4,508,426)	(4,508,426)
Share repurchase program	$ (394)		(394)
Share-based compensation (in shares)		1,528,293
Share-based compensation	$ 69		69
Stock option exercises, net (in shares)	118,094	118,094
Stock option exercises, net	$ 3		3
Other issuances of common stock, net (in shares)		(406,134)
Other issuances of common stock, net	(36)		14	(50)
Issuance of Nasdaq common stock related to a prior acquisition (in shares)		992,247
Common stock, shares outstanding (in shares) at Dec. 31, 2018		165,165,104
Balance at Dec. 31, 2018	$ 5,449	$ 2	$ 2,716	$ (297)	$ (1,530)	$ 4,558

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 458	$ 729	$ 106
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	210	188	170
Share-based compensation	69	70	86
Deferred income taxes	301	7	(137)
Reversal of certain Swedish tax benefits	41	0	0
Net gain on divestiture of businesses	(33)	0	0
Gain on sale of investment security	(118)	0	0
Asset impairment charge	0	0	578
Net income from unconsolidated investees	(18)	(15)	(2)
Other reconciling items included in net income	15	25	17
Net change in operating assets and liabilities, net of effects of divestiture and acquisitions:
Receivables, net	(35)	11	73
Other assets	(40)	(30)	(52)
Accounts payable and accrued expenses	33	(12)	5
Section 31 fees payable to SEC	(19)	20	5
Accrued personnel costs	37	(41)	27
Deferred revenue	7	(29)	(75)
Other liabilities	120	(14)	(25)
Net cash provided by operating activities	1,028	909	776
Cash flows from investing activities:
Purchases of securities	(421)	(392)	(468)
Proceeds from sales and redemptions of securities	374	424	411
Proceeds from divestiture of businesses, net	286	0	0
Proceeds from sale of investment security	169	0	0
Acquisition of businesses, net of cash and cash equivalents acquired and other investment activities	(101)	(778)	(1,466)
Purchases of property and equipment	(111)	(144)	(134)
Net cash provided by (used in) investing activities	196	(890)	(1,657)
Cash flows from financing activities:
Proceeds from (repayments of) commercial paper, net	(205)	480	0
Repayments of long-term debt	(115)	(708)	(1,156)
Payment of debt extinguishment cost	0	(9)	0
Proceeds from long-term debt issuances, net of debt issuance costs	0	648	2,456
Repurchases of common stock	(394)	(203)	(100)
Dividends paid	(280)	(243)	(200)
Proceeds received from employee stock activity	17	53	54
Payments related to employee shares withheld for taxes	(50)	(71)	(65)
Proceeds of customer funds	0	0	(38)
Other financing activities	0	0	(3)
Net cash (used in) provided by financing activities	(1,027)	(53)	948
Effect of exchange rate changes on cash and cash equivalents and restricted cash	(10)	15	(6)
Net increase (decrease) in cash and cash equivalents and restricted cash	187	(19)	61
Cash and cash equivalents and restricted cash at beginning of period	399	418	357
Cash and cash equivalents and restricted cash at end of period	586	399	418
Cash paid for:
Interest	148	129	119
Income taxes, net of refund	$ 221	$ 154	$ 191

Organization and Nature of Operations

12 Months Ended

Dec. 31, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Nature of Operations

Nasdaq, Inc. is a leading provider of trading, clearing, marketplace technology, regulatory, securities listing, information and public and private company services. Our global offerings are diverse and include trading and clearing across multiple asset classes, trade management services, market data products, financial indexes, investment data and analytics, capital formation solutions, corporate solutions, and market technology products and services. Our technology powers markets across the globe, supporting equity derivative trading, clearing and settlement, cash equity trading, fixed income trading, trading surveillance and many other functions.

We manage, operate and provide our products and services in four business segments: Market Services, Corporate Services, Information Services and Market Technology.

Market Services

Our Market Services segment includes our Equity Derivative Trading and Clearing, Cash Equity Trading, FICC and Trade Management Services businesses. We operate multiple exchanges and other marketplace facilities across several asset classes, including derivatives, commodities, cash equity, debt, structured products and ETPs. In addition, in some countries where we operate exchanges, we also provide broker services, clearing, settlement and central depository services. Our transaction-based platforms provide market participants with the ability to access, process, display and integrate orders and quotes. The platforms allow the routing and execution of buy and sell orders as well as the reporting of transactions, providing fee-based revenues.

In the U.S., we operate six electronic options exchanges and three cash equity exchanges. The Nasdaq Stock Market, the largest of our cash equities exchanges, is the largest single venue of liquidity for trading U.S.-listed cash equities. We also operate an electronic platform for trading of U.S. Treasuries and NFX, a U.S. based designated contract market which lists cash-settled energy derivatives based on key energy benchmarks including oil, natural gas and U.S. power. In addition, we also operate a Canadian exchange for the trading of Canadian-listed securities.

In Europe, we operate exchanges in Stockholm (Sweden), Copenhagen (Denmark), Helsinki (Finland), and Reykjavik (Iceland), as well as the clearing operations of Nasdaq Clearing, as Nasdaq Nordic. We also operate exchanges in Tallinn (Estonia), Riga (Latvia) and Vilnius (Lithuania) as Nasdaq Baltic. Collectively, Nasdaq Nordic and Nasdaq Baltic offer trading in cash equities, depository receipts, warrants, convertibles, rights, fund units and ETFs, as well as trading and clearing of derivatives and clearing of resale and repurchase agreements.

Nasdaq Commodities is the brand name for Nasdaq’s European commodity-related products and services. Nasdaq Commodities’ offerings include derivatives in oil, power, natural gas and carbon emission markets, seafood, electricity certificates and clearing services. These products are listed on two of Nasdaq’s derivatives exchanges, Nasdaq Oslo ASA and NFX.

Through our Trade Management Services business, we provide market participants with a wide variety of alternatives for connecting to and accessing our markets via a number of different protocols used for quoting, order entry, trade reporting, and connectivity to various data feeds. We also provide data center services, including co-location to market participants, whereby we offer firms cabinet space and power to house their own servers and other equipment within our data centers. Our broker services operations offer technology and customized securities administration solutions to financial participants in the Nordic market.

Corporate Services

Our Corporate Services segment includes our Corporate Solutions and Listing Services businesses.

Our Corporate Solutions business serves corporate clients, including companies listed on our exchanges and private companies. We help organizations enhance their ability to understand and expand their global shareholder base, and improve corporate governance through our suite of advanced technology, analytics, and consultative services. In April 2018, we sold our Public Relations Solutions and Digital Media Services businesses. See “2018 Divestiture,” of Note 3, “Acquisitions and Divestiture,” for further discussion. As of December 31, 2018, our Corporate Solutions business included our investor relations intelligence, board & leadership and our governance, risk & compliance products and services.

For segment reporting purposes, we have included the revenues and expenses of the Public Relations Solutions and Digital Media Services businesses in corporate items, which were part of the Corporate Solutions business, within our Corporate Services segment, prior to the date of sale. See Note 20, “Business Segments,” for further discussion.

In early 2018, we realigned our businesses to better serve the needs of our corporate clients. As a result, beginning in the second quarter of 2018, our BWise internal audit, regulatory compliance management, and operational risk management software solutions are now offered as part of governance, risk & compliance products and services within our Corporate Solutions business. BWise was previously part of our Market Technology segment.

As of December 31, 2018, BWise has been classified as held for sale. See Note 5, “Assets and Liabilities Held for Sale,” for further discussion. In February 2019, we entered into an agreement to sell BWise. See “Agreement to Sell BWise,” of Note 21, “Subsequent Events,” for further discussion.

Our Listing Services business includes our U.S. and European Listing Services businesses. We operate a variety of listing platforms around the world to provide multiple global capital raising solutions for private and public companies. Our main listing markets are The Nasdaq Stock Market and the Nasdaq Nordic and Nasdaq Baltic exchanges. Through Nasdaq First North, our Nordic and Baltic operations also offer alternative marketplaces for smaller companies and growth companies. Our Listing Services business also includes NPM, which provides liquidity solutions for private companies and private funds.

In December 2018, we launched a Corporate Bond exchange for the listing and trading of corporate bonds. The new exchange operates pursuant to The Nasdaq Stock Market exchange license and is powered by the Nasdaq Financial Framework, similar to the Nasdaq Fixed Income platform. Surveillance is conducted by the Nasdaq regulatory team, assisted by our SMARTS surveillance solution.

As of December 31, 2018, there were 3,058 total listings on The Nasdaq Stock Market, including 392 ETPs. The combined market capitalization was approximately $11.1 trillion. In Europe, the Nasdaq Nordic and Nasdaq Baltic exchanges, together with Nasdaq First North, were home to 1,019 listed companies with a combined market capitalization of approximately $1.3 trillion.

Information Services

Beginning in the second quarter of 2018, our Information Services segment was recategorized into the following businesses:


•	Market Data;


•	Index; and


•	Investment Data & Analytics.

Prior to the second quarter, our Information Services segment was comprised of our Data Products and our Index Licensing and Services businesses.

Our Market Data business sells and distributes historical and real-time quote and trade information to the sell-side, the buy-side, retail online brokers, proprietary trading shops, other venues, internet portals and data distributors. Our market data products enhance transparency of market activity within our exchanges and provide critical information to professional and non-professional investors globally.

Our Index business develops and licenses Nasdaq-branded indexes, associated derivatives, and financial products and also provides custom calculation services for third-party clients. As of December 31, 2018, we had 365 ETPs licensed to Nasdaq’s indexes which had $172 billion in assets under management.

Our Investment Data & Analytics business is a leading content and analytics cloud-based solutions provider used by asset managers, investment consultants and asset owners to help facilitate better investment decisions. Additionally, the Nasdaq Fund Network gathers and distributes daily net asset values from over 35,000 funds and other investment vehicles across North America.

Market Technology

Our Market Technology segment is a leading global technology solutions provider and partner to exchanges, clearing organizations, central securities depositories, regulators, banks, brokers, buy-side firms and corporate businesses. Our Market Technology business is the sales channel for our complete global offering to other marketplaces.

Market Technology provides technology solutions for trading, clearing, settlement, surveillance and information dissemination to markets with wide-ranging requirements, from the leading markets in the U.S., Europe and Asia to emerging markets in the Middle East, Latin America, and Africa. Our marketplace solutions can handle a wide array of assets, including cash equities, equity derivatives, currencies, various interest-bearing securities, commodities and energy products, and are currently powering more than 100 marketplaces in 50 countries. Market Technology also provides market surveillance services to broker-dealer firms worldwide, as well as risk management solutions.

As discussed above under “Corporate Services,” as of the second quarter of 2018, our BWise business, which was previously part of our Market Technology segment, is now offered as part of our Corporate Solutions business.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The consolidated financial statements are prepared in accordance with U.S. GAAP and include the accounts of Nasdaq, its wholly-owned subsidiaries and other entities in which Nasdaq has a controlling financial interest. When we do not have a controlling interest in an entity but exercise significant influence over the entity’s operating and financial policies, such investment is accounted for under the equity method of accounting. We recognize our share of earnings or losses of an equity method investee based on our ownership percentage. See “Equity Method Investments,” of Note 6, “Investments,” for further discussion of our equity method investments.

The accompanying consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair statement of the results. These adjustments are of a normal recurring nature. All significant intercompany accounts and transactions have been eliminated in consolidation.

Certain prior year amounts have been reclassified to conform to the current year presentation. On January 1, 2018, we adopted Topic 606 using the full retrospective method which required restatement of 2017 and 2016 financial statements.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts and the disclosure of contingent amounts in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.

Foreign Currency

Foreign denominated assets and liabilities are remeasured into the functional currency at exchange rates in effect at the balance sheet date and recorded through the income statement. Gains or losses resulting from foreign currency transactions are remeasured using the rates on the dates on which those elements are recognized during the period, and are included in general, administrative and other expense in the Consolidated Statements of Income.

Translation gains or losses resulting from translating our subsidiaries’ financial statements from the local functional currency to the reporting currency, net of tax, are included in accumulated other comprehensive loss within stockholders’ equity in the Consolidated Balance Sheets. Assets and liabilities are translated at the balance sheet date while revenues and expenses are translated at the date the transaction occurs or at an applicable average rate.

Cash and Cash Equivalents

Cash and cash equivalents include all non-restricted cash in banks and highly liquid investments with original maturities of 90 days or less at the time of purchase. Such equivalent investments included in cash and cash equivalents in the Consolidated Balance Sheets were $198 million as of December 31, 2018 and $183 million as of December 31, 2017. Cash equivalents are carried at cost plus accrued interest, which approximates fair value due to the short maturities of these investments.

Restricted Cash

Current restricted cash, which was $41 million as of December 31, 2018 and $22 million as of December 31, 2017, is restricted from withdrawal due to a contractual or regulatory requirement or not available for general use and is classified as restricted cash in the Consolidated Balance Sheets. As of December 31, 2018 and 2017, current restricted cash primarily includes restricted cash held for our trading and clearing businesses.

Receivables, net

Our receivables are concentrated with our member firms, market data distributors, listed companies, corporate solutions and market technology customers. Receivables are shown net of a reserve for uncollectible accounts. The reserve for bad debts is maintained at a level that management believes to be sufficient to absorb estimated losses in the accounts receivable portfolio. The reserve is increased by the provision for bad debts which is charged against operating results and decreased by the amount of charge-offs, net of recoveries. The provision for bad debts is included in general, administrative and other expense in the Consolidated Statements of Income. The amount charged against operating results is based on several factors including, but not limited to, the length of time a receivable is past due and our historical experience with the particular customer. In circumstances where a specific customer’s inability to meet its financial obligations is known (i.e., bankruptcy filings), we record a specific provision for bad debts against amounts due to reduce the receivable to the amount we reasonably believe will be collected. Accounts receivable are written-off against the reserve for bad debts when collection efforts cease. Due to changing economic, business and market conditions, we review the reserve for bad debts monthly and make changes to the reserve through the provision for bad debts as appropriate. If circumstances change (i.e., higher than expected defaults or an unexpected material adverse change in a major customer’s ability to pay), our estimates of recoverability could be reduced by a material amount. The total reserve netted against receivables in the Consolidated Balance Sheets was $13 million as of December 31, 2018, $9 million as of December 31, 2017 and $13 million as of December 31, 2016. The changes in the balance between periods was immaterial.

Investments

Purchases and sales of investment securities are recognized on settlement date.

Financial investments, at fair value

Financial investments, at fair value are primarily comprised of highly rated European government debt securities bought principally to meet regulatory capital requirements mainly for our clearing operations at Nasdaq Clearing. These investments are classified as trading securities as they are generally sold in the near term. Changes in fair value of trading securities are included in other investment income. Debt securities that are classified as available-for-sale investment securities are primarily comprised of commercial paper and are carried at fair value with unrealized gains and losses, net of tax, reported in accumulated other comprehensive loss within stockholders’ equity in the Consolidated Balance Sheets. Realized gains and losses on these securities are included in earnings upon disposition of the securities using the specific identification method. In addition, realized losses are recognized when management determines that a decline in value is other than temporary, which requires judgment regarding the amount and timing of recovery. For financial investments that are classified as available-for-sale securities, we also consider the extent to which cost exceeds fair value, the duration of that difference, management’s judgment about the issuer’s current and prospective financial condition, as well as our intent and ability to hold the security until recovery of the unrealized losses.

Fair value of both trading and available-for-sale investment securities is generally obtained from third party pricing sources. When available, quoted market prices are used to determine fair value. If quoted market prices are not available, fair values are estimated using pricing models with observable market inputs. The inputs to the valuation models vary by the type of security being priced but are typically benchmark yields, reported trades, broker-dealer quotes, and prices of similar assets. Pricing models generally do not entail material subjectivity because the methodologies employed use inputs observed from active markets. See “Fair Value Measurements,” below for further discussion of fair value measures.

Equity Securities

Our investments in equity securities are included in other non-current assets in the Consolidated Balance Sheets, as we intend to hold these investments for more than one year. On January 1, 2018, we adopted ASU 2016-01 which requires that investments in equity securities (excluding equity method investments) be measured at fair value with changes in fair value recognized in net income. Equity securities are no longer classified as trading or available-for-sale.

We elected the measurement alternative for equity securities which were historically accounted for under the cost method of accounting. Since these equity securities do not have readily determinable fair values, they are measured at cost, less any impairment, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. We assess relevant transactions that occur on or before the balance sheet date to identify observable price changes, and we regularly monitor these investments to evaluate whether there is an indication that the investment is impaired, based on the implied value of recent company financings, public market prices of comparable companies, and general market conditions. If a qualitative assessment indicates that the security is impaired, Nasdaq will estimate the fair value of the security, and if the fair value is less than the carrying amount of the security, recognize an impairment loss in net income equal to the difference between the carrying amount and fair value. There was no impact on our consolidated financial statements as a result of this change. For the years ended December 31, 2018, 2017 and 2016, no impairment charges were recorded on our equity securities and there were no upward or downward adjustments recorded.

Equity Method Investments

In general, the equity method of accounting is used when we own 20% to 50% of the outstanding voting stock of a company or when we are able to exercise significant influence over the operating and financial policies of a company. We have certain investments in which we have determined that we have significant influence and as such account for the investments under the equity method of accounting. We record our pro-rata share of earnings or losses each period and record any dividends as a reduction in the investment balance. We evaluate our equity method investments for other-than-temporary declines in value by considering a variety of factors such as the earnings capacity of the investment and the fair value of the investment compared to its carrying amount. In addition, for investments where the market value is readily determinable, we consider the underlying stock price. If the estimated fair value of the investment is less than the carrying amount and management considers the decline in value to be other than temporary, the excess of the carrying amount over the estimated fair value is recognized in the financial statements as an impairment. In 2016, we recorded a pre-tax, non-cash impairment charge of $7 million to write off the full value of an equity method investment since the fair value of the investment was less than the carrying value and management considered the decline in value to be other-than-temporary. This charge is partially offset by a gain resulting from the sale of a percentage of a separate equity method investment and is recorded in net income from unconsolidated investees in the Consolidated Statements of Income for 2016. No other impairments of equity method investments were recorded in 2018, 2017 or 2016.

Default Funds and Margin Deposits

Nasdaq Clearing members’ cash contributions are included in default funds and margin deposits in the Consolidated Balance Sheets as both a current asset and a current liability. These balances may fluctuate over time due to changes in the amount of deposits required and whether members choose to provide cash or non-cash contributions. Non-cash contributions include highly rated government debt securities that must meet specific criteria approved by Nasdaq Clearing. Non-cash contributions are pledged assets that are not recorded in the Consolidated Balance Sheets as Nasdaq Clearing does not take legal ownership of these assets and the risks and rewards remain with the clearing members.

Derivative Financial Instruments and Hedging Activities

Non-Designated Derivatives

We use foreign exchange forward contracts to manage foreign currency exposure of intercompany loans, accounts receivable, accounts payable and other balance sheet items. These contracts are not designated as hedges for financial reporting purposes. The change in fair value of these contracts is recognized in general, administrative and other expense in the Consolidated Statements of Income and offsets the foreign currency exposure.

As of December 31, 2018 and 2017, the fair value amounts of our derivative instruments were immaterial.

Net Investment Hedges

Net assets of our foreign subsidiaries are exposed to volatility in foreign currency exchange rates. We may utilize net investment hedges to offset the translation adjustment arising from re-measuring our investment in foreign subsidiaries.

Our 2021 and 2023 Notes have been designated as a hedge of our net investment in certain foreign subsidiaries to mitigate the foreign exchange risk associated with certain investments in these subsidiaries. Any increase or decrease related to the remeasurement of the 2021 and 2023 Notes into U.S. dollars is recorded in accumulated other comprehensive loss within stockholders’ equity in the Consolidated Balance Sheets. See “3.875% Senior Unsecured Notes,” and “1.75% Senior Unsecured Notes,” of Note 9, “Debt Obligations,” for further discussion.

Property and Equipment, net

Property and equipment, including leasehold improvements, are carried at cost less accumulated depreciation and amortization. Depreciation and amortization are recognized using the straight-line method over the estimated useful lives of the related assets, which range from 10 to 40 years for buildings and improvements, 2 to 5 years for data processing equipment, and 5 to 10 years for furniture and equipment.

We develop systems solutions for both internal and external use. Certain costs incurred in connection with developing or obtaining internal use software are capitalized. In addition, certain costs of computer software to be sold, leased, or otherwise marketed as a separate product or as part of a product or process are capitalized beginning when a product’s technological feasibility has been established and ending when a product is available for general release. Technological feasibility is established upon completion of a detailed program design or, in its absence, completion. Prior to reaching technological feasibility, all costs are charged to expense. Unamortized capitalized costs are included in data processing equipment and software, within property and equipment, net in the Consolidated Balance Sheets. Capitalized software costs are amortized on a straight-line basis over the estimated useful lives of the software, generally 3 to 5 years. Amortization of these costs is included in depreciation and amortization expense in the Consolidated Statements of Income.

Leasehold improvements are amortized using the straight-line method over the shorter of their estimated useful lives or the remaining term of the related lease.

See Note 7, “Property and Equipment, net,” for further discussion.

Goodwill and Indefinite-Lived Intangible Assets

Goodwill represents the excess of purchase price over the value assigned to the net assets, including identifiable intangible assets, of a business acquired. Goodwill is assessed for impairment annually in the fourth quarter of our fiscal year using an October 1 measurement date, or more frequently if conditions exist that indicate that the asset may be impaired, such as changes in the business climate, poor indicators of operating performance or the sale or disposition of a significant portion of a reporting unit. When testing goodwill for impairment, we have the option of first performing a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as the basis to determine if it is necessary to perform a quantitative goodwill impairment test. In performing a qualitative assessment, we consider the extent to which unfavorable events or circumstances identified, such as changes in economic conditions, industry and market conditions or company specific events, could affect the comparison of the reporting unit’s fair value with its carrying amount. If we choose not to complete a qualitative assessment for a given reporting unit, or if the initial assessment indicates that it is more likely than not that the carrying amount of a reporting unit exceeds its estimated fair value, a quantitative test is required.

When assessing goodwill for impairment, our decision to perform a qualitative impairment assessment for a reporting unit in a given year is influenced by a number of factors, including but not limited to, the size of the reporting unit’s goodwill, the significance of the excess of the reporting unit’s estimated fair value over its carrying amount at the last quantitative assessment date, and the amount of time in between quantitative fair value assessments.

The quantitative goodwill test consists of two steps:


•	The first step compares the fair value of each reporting unit with its carrying amount, including goodwill. If the reporting unit’s fair value exceeds its carrying amount, goodwill is not impaired.


•	If the fair value of a reporting unit is less than its carrying amount, the second step of the goodwill test is performed to measure the amount of impairment, if any. An impairment is equal to the excess of the carrying amount of goodwill over its fair value.

We also evaluate indefinite-lived intangible assets for impairment annually in the fourth quarter of our fiscal year using an October 1 measurement date, or more frequently whenever events or changes in circumstances indicate that the fair value of the asset may be less than its carrying amount. Such evaluation includes determining the fair value of the asset and comparing the fair value of the asset with its carrying amount. If the fair value of the indefinite-lived intangible asset is less than its carrying amount, an impairment charge is recognized in an amount equal to the difference.

For indefinite-lived intangible assets impairment testing, we also have the option to first perform a qualitative assessment to determine whether it is more likely than not that the fair value of an indefinite-lived intangible asset is less than the carrying amount. If, after assessing the totality of events or circumstances, we determine that it is more likely than not that the fair value of an indefinite-lived intangible asset is less than its carrying amount, then we must perform additional testing of the asset. Otherwise, we conclude that no impairment is indicated and further testing is not performed.

There was no impairment of goodwill for the years ended December 31, 2018, 2017 and 2016 and there were no indefinite-lived intangible asset impairment charges in 2018 and 2017. In 2016, we recorded a pre-tax, non-cash indefinite-lived intangible asset impairment charge of $578 million to write off the full value of a trade name from an acquired business due to a continued decline in the operating performance of the business during 2016 and a rebranding of our fixed income business under a single brand called Nasdaq Fixed Income. This charge is recorded in asset impairment charge in the Consolidated Statements of Income for 2016. There were no other impairments of indefinite-lived intangible assets for the year ended December 31, 2016. Disruptions to our business and events, such as economic weakness or unexpected significant declines in the operating results of any of our reporting units or businesses, may result in goodwill or indefinite-lived intangible asset impairment charges in the future.

Valuation of Other Long-Lived Assets

We review our other long-lived assets, such as finite-lived intangible assets and property and equipment, for potential impairment when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The carrying amount of an asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the asset. Fair value of finite-lived intangible assets and property and equipment is based on various valuation techniques. Any required impairment loss is measured as the amount by which the carrying amount of the asset exceeds its fair value and is recorded as a reduction in the carrying amount of the related asset and a charge to operating results. We recorded pre-tax, non-cash property and equipment asset impairment charges of $9 million in 2017 and $8 million in 2016. The impairment charge in 2017 primarily related to the write-off of capitalized software and hardware equipment associated with our 2017 and 2016 acquisitions and is included in merger and strategic initiatives expense in the Consolidated Statements of Income for 2017. The asset impairment charge in 2016 primarily related to fixed assets and capitalized software that were retired and is included in restructuring charges in the Consolidated Statements of Income for 2016. There were no other impairments of property and equipment recorded in 2018, 2017 or 2016.

Revenue Recognition and Transaction-Based Expenses

Revenue From Contracts With Customers

On January 1, 2018, we adopted Topic 606 using the full retrospective method. The adoption of Topic 606 impacted the revenue and expense recognition for our Market Technology business and revenue recognition for our Listing Services business. However, the adoption of Topic 606 did not have a material impact on our consolidated financial statements at the time of adoption or in any prior reporting periods. There was no impact to revenue and expense recognition for our other businesses.

As of January 1, 2016, as a result of the adoption of Topic 606, the impact to retained earnings was immaterial. The following tables present the adjustments to reflect the adoption of Topic 606 on our Consolidated Statements of Income for the years ended December 31, 2017 and 2016 and our Consolidated Balance Sheets as of December 31, 2017 and 2016:



Adjustments to Reflect Adoption of Topic 606
	Year Ended December 31,
	2017			2016
	(in millions)
Revenues less transaction-based expenses:
Market Services	$	—		$	—
Corporate Services	(3		)	(3		)
Information Services	—			—
Market Technology	(14		)	2
Total revenues less transaction-based expenses	$	(17	)	$	(1	)

Total operating expenses⁽¹⁾	$	(9	)	$	2

Income before income taxes	$	(8	)	$	(3	)
Income tax provision	(3		)	(1		)
Net income attributable to Nasdaq	$	(5	)	$	(2	)
Diluted earnings per share	$	(0.03	)	$	(0.01	)

____________

⁽¹⁾ Adjustment to reflect the adoption of Topic 606 for the year ended December 31, 2017 and 2016 primarily pertain to our Market Technology business.



Adjustments to Reflect Adoption of Topic 606
	December 31, 2017			December 31, 2016
	(in millions)
Assets:
Other current assets	$	(19	)	$	(15	)
Other non-current assets	(38		)	(46		)
Deferred tax assets	2			(1		)
Total assets	$	(55	)	$	(62	)

Liabilities:
Deferred revenue	$	(28	)	$	(24	)
Non-current deferred revenue	(20		)	(36		)
Total liabilities	(48		)	(60		)

Nasdaq stockholders' equity:
Retained earnings	$	(7	)	$	(2	)
Total Nasdaq stockholders' equity	(7		)	(2		)

Total liabilities and equity	$	(55	)	$	(62	)

Additional disclosures required by Topic 606 are provided below.

Contract Balances

Substantially all of our revenues are considered to be revenues from contracts with customers. The related accounts receivable balances are recorded in our Consolidated Balance Sheets as receivables which is net of allowance for doubtful accounts of $13 million as of December 31, 2018 and $9 million as of December 31, 2017. The changes in the balance between periods were immaterial. We do not have obligations for warranties, returns or refunds to customers.

For the majority of our contracts with customers, except for our market technology and listings services contracts, our performance obligations are short-term in nature and there is no significant variable consideration.

We do not have revenues recognized from performance obligations that were satisfied in prior periods. We have elected not to provide disclosures about transaction price allocated to unsatisfied performance obligations if contract durations are less than one year. For contract durations that are one-year or greater, we do not have a material portion of transaction price allocated to unsatisfied performance obligations that are not included in deferred revenue other than for our market technology contracts which are discussed below under “Market Technology.” Deferred revenue primarily represents our contract liabilities related to our fees for annual and initial listings, market technology, corporate solutions and information services contracts. Deferred revenue is the only significant contract asset or liability impacted by our adoption of Topic 606. See Note 8, “Deferred Revenue,” for our discussion on deferred revenue balances, activity, and expected timing of recognition. See “Revenue Recognition” below for further descriptions of our revenue contracts.

Sales commissions earned by our sales force are considered incremental and recoverable costs of obtaining a contract with a customer. These costs are deferred and amortized on a straight-line basis over the period of benefit that we have determined to be the contract term or estimated service periods. Sales commissions for renewal contracts are deferred and amortized on a straight-line basis over the related contractual renewal period. Amortization expense is included in compensation and benefits expense in the Consolidated Statements of Income. The balance of deferred costs and related amortization expense are not material to our consolidated financial statements. We elected the practical expedient of recognizing sales commissions as an expense when incurred if contract durations are one year or less. We also have elected the practical expedient of excluding sales taxes from transaction prices.

Certain judgments and estimates were used in the identification and timing of satisfaction of performance obligations and the related allocation of transaction price and are discussed below. We believe that these represent a faithful depiction of the transfer of services to our customers.

Revenue Recognition

Our primary revenue contract classifications are described below. Though we discuss additional revenue details in our “Management's Discussion and Analysis of Financial Condition and Results of Operations,” the categories below best represent those that depict similar economic characteristics of the nature, amount, timing and uncertainty of our revenues and cash flows.

Market Services

Transaction-Based Trading and Clearing

Transaction-based trading and clearing includes equity derivative trading and clearing, cash equity trading and FICC revenues. Nasdaq charges transaction fees for trades executed on our exchanges, as well as on orders that are routed to and executed on other market venues. Nasdaq charges clearing fees for contracts cleared with Nasdaq Clearing.

In the U.S., transaction fees are based on trading volumes for trades executed on our U.S. exchanges and in Europe, transaction fees are based on the volume and value of traded and cleared contracts. In Canada, transaction fees are based on trading volumes for trades executed on our Canadian exchange.

Nasdaq satisfies its performance obligation for trading services upon the execution of a customer trade and clearing services when a contract is cleared, as trading and clearing transactions are substantially complete when they are executed and we have no further obligation to the customer at that time. Transaction-based trading and clearing fees can be variable and are based on trade volume tiered discounts. Transaction revenues, as well as any tiered volume discounts, are calculated and billed monthly in accordance with our published fee schedules. In the U.S., we also pay liquidity payments to customers based on our published fee schedules. We use these payments to improve the liquidity on our markets and therefore recognize those payments as a cost of revenue.

The majority of our FICC trading and clearing customers are charged transaction fees, as discussed above, which are based on the volume and value of traded and cleared contracts. We also enter into annual fixed contracts with customers trading U.S. Treasury securities. The customers are charged an annual fixed fee which is billed per the agreement, on a monthly or quarterly basis. Revenues earned on fixed contracts are recognized over time on a ratable basis over the contract period beginning on the date that our service is made available to the customer since the customer receives and consumes the benefit as Nasdaq provides the service.

For U.S. equity derivative trading, we credit a portion of the per share execution charge to the market participant that provides the liquidity. For U.S. cash equity trading, for Nasdaq and Nasdaq PSX, we credit a portion of the per share execution charge to the market participant that provides the liquidity and for Nasdaq BX, we credit a portion of the per share execution charge to the market participant that takes the liquidity. We record these credits as transaction rebates that are included in transaction-based expense in the Consolidated Statements of Income. These transaction rebates are paid on a monthly basis and the amounts due are included in accounts payable and accrued expenses in the Consolidated Balance Sheets.

In the U.S., we pay Section 31 fees to the SEC for supervision and regulation of securities markets. We pass these costs along to our customers through our equity derivative trading and clearing fees and our cash equity trading fees. We collect the fees as a pass-through charge from organizations executing eligible trades on our options exchanges and our cash equity platforms and we recognize these amounts in transaction-based expenses when incurred. Section 31 fees received are included in cash and cash equivalents in the Consolidated Balance Sheets at the time of receipt and, as required by law, the amount due to the SEC is remitted semiannually and recorded as Section 31 fees payable to the SEC in the Consolidated Balance Sheets until paid. Since the amount recorded as revenues is equal to the amount recorded as transaction-based expenses, there is no impact on our revenues less transaction-based expenses. As we hold the cash received until payment to the SEC, we earn interest income on the related cash balances.

Under our Limitation of Liability Rule and procedures, we may, subject to certain caps, provide compensation for losses directly resulting from the systems’ actual failure to correctly process an order, quote, message or other data into our platform. We do not record a liability for any potential claims that may be submitted under the Limitation of Liability Rule unless they meet the provisions required in accordance with U.S. GAAP. As such, losses arising as a result of the rule are accrued and charged to expense only if the loss is probable and estimable.

Trade Management Services

We provide market participants with a wide variety of alternatives for connecting to and accessing our markets for a fee. We also offer market participants co-location services, whereby we charge firms for cabinet space and power to house their own equipment and servers within our data centers. These participants are charged monthly fees for cabinet space, connectivity and support in accordance with our published fee schedules. These fees are recognized on a monthly basis when the performance obligation is met. We also earn revenues from annual and monthly exchange membership and registration fees. Revenues for providing access to our markets, co-location services and monthly exchange membership and registration fees are recognized on a monthly basis as the service is provided. Revenues from annual fees for exchange membership and registration fees are recognized ratably over the following 12-month period since the customer receives and consumes the benefit as Nasdaq provides the service. We also offer broker services to financial participants in the Nordic market primarily providing flexible back-office systems, which allow customers to entirely or partly outsource their company’s back-office functions. Revenues from broker services are based on a fixed basic fee for administration or licensing, maintenance and operations, and an incremental fee depending on the number of transactions completed. Broker services revenues are generally billed and recognized monthly.

Corporate Services

Corporate Solutions

As of December 31, 2018, corporate solutions revenues primarily include subscription and transaction-based income from our investor relations intelligence, board & leadership and governance, risk & compliance products and services. In April 2018, we completed the sale of our Public Relations Solutions and Digital Media Services businesses. See “2018 Divestiture,” of Note 3, “Acquisitions and Divestiture,” for further discussion. Subscription-based revenues earned are recognized over time on a ratable basis over the contract period beginning on the date that our service is made available to the customer since the customer receives and consumes the benefit as Nasdaq provides the service. Generally, fees are billed quarterly in advance and the contract provides for automatic renewal. As part of the subscription agreements, customers can also be charged usage fees based upon actual usage of the services provided. Revenues from usage fees are recognized at a point in time upon completion of the service.

Listing Services

Listing services revenues primarily include initial listing fees and annual renewal fees. Under Topic 606, the initial listing fee is allocated to multiple performance obligations including initial and subsequent listing services and corporate solutions services (when a company qualifies to receive these services under the applicable Nasdaq rule), as well as a customer's material right to renew the option to list on our exchanges. In performing this allocation, the standalone selling price of the performance obligations is based on the initial and annual listing fees and the standalone selling price of the corporate solutions services is based on its market value. All listing fees are billed upfront and the identified performance obligations are satisfied over time since the customer receives and consumes the benefit as Nasdaq provides the listing service. Upon adoption of Topic 606, the amount of revenue related to the corporate solutions services performance obligation is recognized ratably over a two-year period, which is based on contract terms, with the remaining revenue recognized ratably over six years which is based on our historical listing experience and projected future listing duration.

In the U.S., annual renewal fees are charged based on the number of outstanding shares of companies listed in the U.S. at the end of the prior year and are recognized ratably over the following 12-month period since the customer receives and consumes the benefit as Nasdaq provides the service. European annual renewal fees, which are received from companies listed on our Nasdaq Nordic and Nasdaq Baltic exchanges and Nasdaq First North, are directly related to the listed companies’ market capitalization on a trailing 12-month basis and are recognized ratably over the following 12-month period since the customer receives and consumes the benefit as Nasdaq provides the service.

Information Services

Market Data Products

Market data products revenues are earned from U.S. and European proprietary market data products. In the U.S., we also earn revenues from U.S. shared tape plans.

We earn revenues primarily based on the number of data subscribers and distributors of our data. Market data products revenues are subscription-based and are recognized on a monthly basis net of amounts due under revenue sharing arrangements with market participants.

For U.S. tape plans, revenues are collected monthly based on published fee schedules and distributed quarterly to the U.S. exchanges based on a formula required by Regulation NMS that takes into account both trading and quoting activity. Revenues are presented on a net basis as we are acting as an agent in this arrangement.

Market Data Products Revenue Sharing

The most significant component of market data products revenues recorded on a net basis is the UTP Plan revenue sharing in the U.S. All indicators of principal versus agent reporting under U.S. GAAP have been considered in analyzing the appropriate presentation of the revenue sharing. However, the following are the primary indicators of net reporting:


•	We are the administrator for the plan, in addition to being a participant in the plan. In our unique role as administrator, we facilitate the collection and dissemination of revenues on behalf of the plan participants. As a participant, we share in the net distribution of revenues according to the plan on the same terms as all other plan participants.


•	The operating committee of the plan, which is comprised of representatives from each of the participants, including us solely in our capacity as a plan participant, is responsible for setting the level of fees to be paid by distributors and subscribers and taking action in accordance with the provisions of the plan, subject to SEC approval.


•	Risk of loss on the revenue is shared equally among plan participants according to the plan.

The exchanges that comprise Nasdaq Nordic and Nasdaq Baltic do not have any market data products revenue sharing agreements.

Index

We develop and license Nasdaq branded indexes, associated derivatives and financial products as part of our Global Index Family. We also provide index data products and custom calculation services for third-party clients. Revenues primarily include license fees from these branded indexes, associated derivatives and financial products in the U.S. and abroad. We primarily have two types of license agreements: transaction-based licenses and asset-based licenses. Transaction-based licenses are generally renewable agreements. Customers are charged based on transaction volume or a minimum contract amount, or both. If a customer is charged based on transaction volume, we recognize revenue when the transaction occurs. If a customer is charged based on a minimum contract amount, we recognize revenue on a pro-rata basis over the licensing term since the customer receives and consumes the benefit as Nasdaq provides the service. Asset-based licenses are also generally renewable agreements. Customers are charged based on a percentage of assets under management for licensed products, per the agreement, on a monthly or quarterly basis. These revenues are recognized over the term of the license agreement since the customer receives and consumes the benefit as Nasdaq provides the service. Revenue from index data subscriptions are recognized on a monthly basis.

Investment Data & Analytics

Investment data & analytics revenues are earned from investment content and analytics products. We earn revenues primarily based on the number of content and analytics subscribers and distributors.

Subscription agreements are generally annual in term, payable in advance, and provide for automatic renewal. Subscription-based revenues are recognized over time on a ratable basis over the contract period beginning on the date that our service is made available to the customer since the customer receives and consumes the benefit as Nasdaq provides the service.

Market Technology

Market Technology provides technology solutions for trading, clearing, settlement, surveillance and information dissemination, as well as risk management solutions. Revenues primarily consist of software, license and support revenues, change request and advisory revenues, and software as a service revenues.

In our Market Technology business, we enter into long-term contracts with customers to develop customized technology solutions, license the right to use software, and provide support and other services to our customers. We also enter into agreements to modify the system solutions sold by Nasdaq after delivery has occurred. In addition, we enter into subscription agreements which allow customers to connect to our servers to access our software.

Our long-term contracts with customers to develop customized technology solutions, license the right to use software and provide support and other services to our customers have multiple performance obligations. The performance obligations are generally: 1) software license and installation service and 2) software support. We have determined that the software license and installation service are not distinct as the license and the customized installation service are inputs to produce the combined output, a functional and integrated software system.

For contracts with multiple performance obligations, we allocate the contract transaction price to each performance obligation using our best estimate of the standalone selling price of each distinct good or service in the contract. In instances where standalone selling price is not directly observable, such as when we do not sell the product or service separately, we determine the standalone selling price predominately through an expected cost plus a margin approach.

Contract modifications are routine in the performance of our contracts. Contracts are often modified to account for changes in contract specifications or requirements. In most instances, contract modifications are for goods and services that are not distinct, and, therefore, are accounted for as part of the existing contract.

For our long-term contracts, payments are generally made throughout the contract life and can be dependent on either reaching certain milestones or paid upfront in advance of the service period depending on the stage of the contract. For subscription agreements, contract payment terms can be quarterly, annually or monthly, in advance. For all other contracts, payment terms vary.

We generally recognize revenue over time as our customers simultaneously receive and consume the benefits provided by our performance because our customer controls the asset for which we are creating, our performance does not create an asset with alternative use, and we have a right to payment for performance completed to date. For these services, we recognize revenue over time using costs incurred to date relative to total estimated costs at completion to measure progress toward satisfying our performance obligation. Incurred costs represent work performed, which corresponds with, and thereby depicts, the transfer of control to the customer. Contract costs generally include labor and direct overhead. For software support and update services, and for subscription agreements which allow customers to connect to our servers to access our software, we generally recognize revenue ratably over the service period beginning on the date our service is made available to the customer since the customer receives and consumes the benefit consistently over the period as Nasdaq provides the services.

Accounting for our long-term contracts requires judgment relative to assessing risks and their impact on the estimate of revenues and costs. Our estimates are impacted by factors such as the potential for schedule and technical issues, productivity, and the complexity of work performed. When adjustments in estimated total contract costs are required, any changes in the estimated revenues from prior estimates are recognized in the current period for the effect of such change. If estimates of total costs to be incurred on a contract exceed estimates of total revenues, a provision for the entire estimated loss on the contract is recorded in the period in which the loss is determined.

Other Revenues

Other revenues include the revenues from the Public Relations Solutions and Digital Media Services businesses which were sold in April 2018. Prior to the sale date, these revenues were included in our Corporate Solutions business and were primarily transaction-based revenues.

* * * * * *

As stated above, for contract durations that are one-year or greater, we do not have a material portion of transaction price allocated to unsatisfied performance obligations that are not included in deferred revenue other than for our market technology contracts. For our market technology contracts, the following table summarizes the amount of the transaction price allocated to performance obligations that are unsatisfied as of December 31, 2018:



	(in millions)
2019	$	255
2020	183
2021	94
2022	58
2023	30
2024 and thereafter	75
Total	$	695

Market technology deferred revenue, as discussed in Note 8, “Deferred Revenue,” to the consolidated financial statements, represents consideration received that is yet to be recognized as revenue for unsatisfied performance obligations.

The following tables summarize the disaggregation of revenue by major product and service and by segment for the years ended December 31, 2018, 2017 and 2016:



	Year Ended December 31, 2018
	Market Services		Corporate Services		Information Services		Market Technology		Other Revenues		Consolidated
	(in millions)
Transaction-based trading and clearing, net	$	666	$	—	$	—	$	—	$	—	$	666
Trade management services	292		—		—		—		—		292
Corporate solutions	—		238		—		—		—		238
Listing services	—		290		—		—		—		290
Market data products	—		—		390		—		—		390
Index	—		—		206		—		—		206
Investment data & analytics	—		—		118		—		—		118
Market technology	—		—		—		270		—		270
Other revenues	—		—		—		—		56		56
Revenues less transaction-based expenses	$	958	$	528	$	714	$	270	$	56	$	2,526



	Year Ended December 31, 2017
	Market Services		Corporate Services		Information Services		Market Technology		Other Revenues		Consolidated
	(in millions)
Transaction-based trading and clearing, net	$	590	$	—	$	—	$	—	$	—	$	590
Trade management services	291		—		—		—		—		291
Corporate solutions	—		234		—		—		—		234
Listing services	—		267		—		—		—		267
Market data products	—		—		369		—		—		369
Index	—		—		171		—		—		171
Investment data & analytics	—		—		48		—		—		48
Market technology	—		—		—		247		—		247
Other revenues	—		—		—		—		194		194
Revenues less transaction-based expenses	$	881	$	501	$	588	$	247	$	194	$	2,411



	Year Ended December 31, 2016
	Market Services		Corporate Services		Information Services		Market Technology		Other Revenues		Consolidated
	(in millions)
Transaction-based trading and clearing, net	$	561	$	—	$	—	$	—	$	—	$	561
Trade management services	266		—		—		—		—		266
Corporate solutions	—		208		—		—		—		208
Listing services	—		269		—		—		—		269
Market data products	—		—		354		—		—		354
Index	—		—		149		—		—		149
Investment data & analytics	—		—		37		—		—		37
Market technology	—		—		—		241		—		241
Other revenues	—		—		—		—		191		191
Revenues less transaction-based expenses	$	827	$	477	$	540	$	241	$	191	$	2,276

For the year ended December 31, 2018, approximately 63.6% of Market Services revenues were recognized at a point in time and 36.4% were recognized over time. For the year ended December 31, 2017, approximately 62.7% of Market Services revenues were recognized at a point in time and 37.3% were recognized over time. For the year ended December 31, 2016, approximately 63.4% of Market Services revenues were recognized at a point in time and 36.6% were recognized over time. Substantially all revenues from the Corporate Services, Information Services and Market Technology segments were recognized over time for the years ended December 31, 2018, 2017 and 2016.

* * * * * *

Earnings Per Share

We present both basic and diluted earnings per share. Basic earnings per share is computed by dividing net income attributable to Nasdaq by the weighted-average number of common shares outstanding for the period. Diluted earnings per share is computed by dividing net income attributable to Nasdaq by the weighted-average number of common shares and common share equivalents outstanding during the period and reflects the assumed conversion of all dilutive securities, which primarily consist of employee stock options, restricted stock, and PSUs. Common share equivalents are excluded from the computation in periods for which they have an anti-dilutive effect. Stock options for which the exercise price exceeds the average market price over the period are anti-dilutive and, accordingly, are excluded from the calculation. PSUs, which are considered contingently issuable, are included in the computation of dilutive earnings per share on a weighted average basis when management determines the related performance criteria are met. See Note 13, “Earnings Per Share,” for further discussion.

Pension and Post-Retirement Benefits

Pension and other post-retirement benefit plan information for financial reporting purposes is developed using actuarial valuations. We assess our pension and other post-retirement benefit plan assumptions on a regular basis. In evaluating these assumptions, we consider many factors, including evaluation of the discount rate, expected rate of return on plan assets, mortality rate, healthcare cost trend rate, retirement age assumption, our historical assumptions compared with actual results and analysis of current market conditions and asset allocations. See Note 10, “Retirement Plans,” for further discussion.

Discount rates used for pension and other post-retirement benefit plan calculations are evaluated annually and modified to reflect the prevailing market rates at the measurement date of a high-quality fixed-income debt instrument portfolio that would provide the future cash flows needed to pay the benefits included in the benefit obligations as they come due. Actuarial assumptions are based upon management’s best estimates and judgment.

The expected rate of return on plan assets for our U.S. pension plans represents our long-term assessment of return expectations which may change based on significant shifts in economic and financial market conditions. The long-term rate of return on plan assets is derived from return assumptions based on targeted allocations for various asset classes. While we consider the pension plans’ recent performance and other economic growth and inflation factors, which are supported by long-term historical data, the return expectations for the targeted asset categories represent a long-term prospective return.

Share-Based Compensation

Nasdaq uses the fair value method of accounting for share-based awards. Share-based awards, or equity awards, include stock options, restricted stock, and PSUs. The fair value of stock options are estimated using the Black-Scholes option-pricing model. The fair value of restricted stock awards and PSUs, other than PSUs granted with market conditions, is determined based on the grant date closing stock price less the present value of future cash dividends. We estimate the fair value of PSUs granted with market conditions using a Monte Carlo simulation model at the date of grant.

We generally recognize compensation expense for equity awards on a straight-line basis over the requisite service period of the award, taking into account an estimated forfeiture rate. Granted but unvested shares are generally forfeited upon termination of employment.

Excess tax benefits or expense related to employee share-based payments, if any, are recognized as income tax benefit or expense in the Consolidated Statements of Income when the awards vest or are settled.

Nasdaq also has an ESPP that allows eligible employees to purchase a limited number of shares of our common stock at six-month intervals, called offering periods, at 85.0% of the lower of the fair market value on the first or the last day of each offering period. The 15.0% discount given to our employees is included in compensation and benefits expense in the Consolidated Statements of Income.

See Note 11, “Share-Based Compensation,” for further discussion of our share-based compensation plans.

Merger and Strategic Initiatives

We incur incremental direct merger and strategic initiative costs relating to various completed and potential acquisitions and other strategic opportunities. These costs include outside advisor fees, deal-related bonuses to certain employees, and other external costs directly related to proposed or closed transactions. We also incur integration costs primarily related to employee termination costs, deal-related bonuses and professional services costs incurred relating to the integrations. As of December 31, 2018, all planned integrations for our 2017 and 2016 acquisitions have been completed. For the years ended December 30, 2018 and December 31, 2017, we also incurred costs related to the divestiture of our Public Relations Solutions and Digital Media Services businesses which primarily included outside advisor fees as well as certain employee termination and lease reserves.

Leases

We expense rent from non-cancellable operating leases, net of sublease income, on a straight line basis, based on future minimum lease payments. The net costs are included in occupancy expense in the Consolidated Statements of Income. See Note 16, “Leases,” for further discussion.

In February 2016, the FASB issued ASU 2016-02, “Leases.” We adopted this new guidance on January 1, 2019. See “Leases,” of “Recent Accounting Pronouncements,” below for further discussion.

Fair Value Measurements

Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability, or the exit price, in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities required or permitted to be either recorded or disclosed at fair value, we consider the principal or most advantageous market in which we would transact, and we also consider assumptions that market participants would use when pricing the asset or liability. Fair value measurement establishes a hierarchy of valuation techniques based on whether the inputs to those valuation techniques are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect Nasdaq’s market assumptions. These two types of inputs create the following fair value hierarchy:


•	Level 1-Quoted prices for identical instruments in active markets.


•	Level 2-Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable.


•	Level 3-Instruments whose significant value drivers are unobservable.

This hierarchy requires the use of observable market data when available.

See Note 14, “Fair Value of Financial Instruments,” for further discussion.

Tax Matters

We use the asset and liability method to determine income taxes on all transactions recorded in the consolidated financial statements. Deferred tax assets (net of valuation allowances) and deferred tax liabilities are presented net by jurisdiction as either a non-current asset or liability in our Consolidated Balance Sheets, as appropriate. Deferred tax assets and liabilities are determined based on differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities (i.e., temporary differences) and are measured at the enacted rates that will be in effect when these differences are realized. If necessary, a valuation allowance is established to reduce deferred tax assets to the amount that is more likely than not to be realized.

In order to recognize and measure our unrecognized tax benefits, management determines whether a tax position is more likely than not to be sustained upon examination, including resolution of any related appeals or litigation processes, based on the technical merits of the position. Once it is determined that a position meets the recognition thresholds, the position is measured to determine the amount of benefit to be recognized in the consolidated financial statements. Interest and/or penalties related to income tax matters are recognized in income tax expense.

During the fourth quarter of 2018, we finalized the accounting associated with the December 22, 2017 enactment of The Tax Cuts and Jobs Act. For further discussion of the impacts of the tax act and other tax matters, see Note 17, “Income Taxes,” to the consolidated financial statements.

Assets Held for Sale

We classify assets or disposal groups as held for sale in the period in which all of the following criteria are met:


•	management commits to a plan to sell;


•	the asset or disposal group is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such assets or disposal groups;


•	an active program to locate a buyer and other actions required to complete the plan to sell have been initiated;


•	the sale is probable within one year;


•	the asset or disposal group is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and


•	it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn.

Assets and disposal groups classified as held for sale are measured at the lower of their carrying amount or fair value less costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized until the date of sale. The fair value of an asset less any costs to sell is assessed each reporting period it remains classified as held for sale, and any change in fair value is reported as an adjustment to the carrying value of the asset, except that increases in fair value are limited to prior decreases recorded. Assets are not depreciated or amortized while they are classified as held for sale. See Note 4, “Assets and Liabilities Held For Sale,” for further discussion of our assets held for sale.

Recent Accounting Pronouncements



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Intangibles - Goodwill and Other - Internal-Use Software In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract.”	This ASU clarifies the accounting for implementation costs of a hosting arrangement and aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). Capitalized implementation costs should be expensed over the term of the hosting arrangement and recognized in the same line item in the statement of income as the hosted service costs. Payments for capitalized implementation costs should be classified in the statement of cash flows in the same manner as payments made for fees associated with the hosting element. Capitalized implementation costs should be presented in the balance sheet in the same line item as a prepayment for the fees of the associated hosting arrangement.	January 1, 2020, with early adoption permitted. We early adopted this standard as of July 1, 2018.	There was no impact to the financial statements as a result of the adoption of this standard, as we are currently accounting for costs incurred in a cloud computing arrangement in accordance with the standard.
Fair Value Measurements In August 2018, the FASB issued ASU 2018-13 “Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement.”	This ASU modifies the disclosure requirements on fair value measurements by removing certain disclosure requirements related to the fair value hierarchy, modifying existing disclosure requirements related to measurement uncertainty, and adding new requirements, mainly for Level 3 fair value measurements.	January 1, 2020, with early adoption permitted. We early adopted this standard as of July 1, 2018 on a prospective basis.	There was no impact to the financial statements or our disclosures as a result of the adoption of this standard.



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Income Statement - Reporting Comprehensive Income In February 2018, the FASB issued ASU 2018-02, “Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (Topic 220).”	This ASU was issued to address the income tax accounting treatment of the stranded tax effects within other comprehensive income due to the prohibition of backward tracing due to an income tax rate change that was initially recorded in other comprehensive income. This issue came about from the enactment of the Tax Cuts and Jobs Act that changed our income tax rate from 35% to 21%. The ASU changed current accounting whereby an entity may elect to reclassify the stranded tax effect from accumulated other comprehensive income to retained earnings.	January 1, 2019, with early adoption permitted. We early adopted this standard as of January 1, 2018.	As a result of the adoption of this standard, we recorded a reclassification of $417 million related to the Tax Cuts and Jobs Act from accumulated other comprehensive loss to retained earnings within stockholders’ equity in the Consolidated Balance Sheets. See “Tax Cuts and Jobs Act,” of Note 17, “Income Taxes,” for further discussion.
Goodwill In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment.”	This ASU simplifies how an entity is required to test goodwill for impairment and removes the second step of the goodwill impairment test, which required a hypothetical purchase price allocation if the fair value of a reporting unit is less than its carrying amount. Goodwill impairment will now be measured using the difference between the carrying amount and the fair value of the reporting unit and the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The amendments in this ASU should be applied on a prospective basis.	January 1, 2020, with early adoption permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017.	We do not anticipate a material impact on our consolidated financial statements at the time of adoption of this new standard as the carrying amounts of our reporting units have been less than their corresponding fair values in recent years. However, changes in future projections, market conditions and other factors may cause a change in the excess of fair value of our reporting units over their corresponding carrying amounts. We do not anticipate early adoption of this standard.



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Financial Instruments - Credit Losses In June 2016, the FASB issued ASU 2016-13, “Measurement of Credit Losses on Financial Instruments.”	This ASU changes the impairment model for certain financial instruments. The new model is a forward looking expected loss model and will apply to financial assets subject to credit losses and measured at amortized cost and certain off-balance sheet credit exposures. This includes loans, held-to-maturity debt securities, loan commitments, financial guarantees and net investments in leases, as well as trade receivables. For available-for-sale debt securities with unrealized losses, credit losses will be measured in a manner similar to today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of the securities.	January 1, 2020, with early adoption permitted as of January 1, 2019.	We will adopt this standard on January 1, 2020. We are currently assessing the impact that this standard will have on our consolidated financial statements.
Leases In February 2016, the FASB issued ASU 2016-02, “Leases.”	Under this ASU, at the commencement date, lessees will be required to recognize a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. This guidance is not applicable for leases with a term of 12 months or less. Recognition, measurement and presentation of expenses will depend on classification as a finance or operating lease. The guidance also requires certain quantitative and qualitative disclosures about leasing arrangements. Lessor accounting is largely unchanged. In transition, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach.	January 1, 2019.	See discussion below.

* * * * * *

Leases

We adopted ASU 2016-02 on January 1, 2019. Adoption of the new standard resulted in the recording of a right-of-use asset of $442 million, a lease liability of $483 million, as well as the elimination of deferred rent and sublease reserves of $41 million as of January 1, 2019. The standard did not impact our statements of income and had no impact on our cash flows. Our implementation of this guidance is subject to the same internal controls over financial reporting that we apply to our consolidated financial statements.

Practical Expedients and Accounting Policy Elections

We elected the package of practical expedients permitted under the transition guidance within the standard to not reassess contracts to determine if they contain leases, lease classification and initial direct costs. We also elected the optional transition method to initially apply the standard at the January 1, 2019 adoption date. As a result, we applied the new lease standard prospectively to leases existing or commencing on or after January 1, 2019. Comparative periods presented will not be restated upon adoption. Similarly, new disclosures under the standard will be made for periods beginning January 1, 2019, and not for prior comparative periods. Prior periods will continue to be reported under guidance in effect prior to January 1, 2019. We made an accounting policy election to treat the lease and non-lease components in a contract as a single performance obligation to the extent that the timing and pattern of transfer are similar for the lease and non-lease components and the lease component qualifies as an operating lease. We also made an accounting policy election not to recognize lease liabilities and right-of-use assets for leases with a term of 12 months or less. We will recognize these lease payments on a straight-line basis over the lease term. We did not elect the practical expedient related to using hindsight to reevaluate the lease term. Additionally, since our leases do not provide an implicit rate, we used our incremental borrowing rate based on information available at the transition date utilizing the remaining lease term to determine the present value of future payments.

Acquisitions and Divestiture

12 Months Ended

Dec. 31, 2018

Business Combinations [Abstract]

Acquisitions and Divestiture

2019 Acquisition

Acquisition of Cinnober

In 2018, we made an all cash recommended public offer to the shareholders and warrant holders of Cinnober, a major Swedish financial technology provider to brokers, exchanges and clearinghouses worldwide. In December 2018, we increased our offer to SEK 87 per share and SEK 121 per warrant, or approximately $220 million. In January 2019, Nasdaq completed the offer and as of February 2019 controls approximately 99.6% of the total number of shares in Cinnober. Through compulsory acquisition procedures, Nasdaq intends to acquire 100% of the Cinnober shares outstanding. It is not currently known when the proceedings will be completed and when Nasdaq will be able to acquire the Cinnober shares that are the subject of the proceedings. Cinnober is part of our Market Technology segment.

Nasdaq used cash on hand to fund this acquisition.

2018, 2017 and 2016 Acquisitions and 2018 Divestiture

We completed a divestiture in April 2018 and several acquisitions during the years ended December 31, 2018, 2017 and 2016 and included the financial results of such acquisitions in our consolidated financial statements from the respective acquisition dates.

2018 Acquisitions

Acquisition of Quandl

In November 2018, we acquired Quandl, Inc., a leading provider of alternative and core financial data. Quandl is part of our Information Services segment.

Nasdaq used issuances of commercial paper to fund this acquisition.

Acquisition of RedQuarry

In October 2018, we acquired the assets of RedQuarry. RedQuarry is part of our Information Services segment.

2018 Divestiture

In April 2018, we sold our Public Relations Solutions and Digital Media Services businesses which were part of our Corporate Solutions business to West Corporation and recognized a pre-tax net gain on the sale of $33 million, net of disposal costs ($14 million after tax), which includes a post-closing working capital adjustment of $8 million ($5 million after tax) recorded in September 2018. The total net pre-tax gain is included in net gain on divestiture of businesses in the Consolidated Statements of Income for 2018.

As of December 31, 2017, the assets and liabilities of the above businesses were held for sale. See Note 4, “Assets and Liabilities Held For Sale,” for further discussion.

Through a multi-year partnership with West, Nasdaq will continue to provide eligible Nasdaq-listed clients with access to public relations, webcasting and webhosting products and services as part of the terms of the transaction.

As part of the terms of the transaction, we are providing transition services to West, such as technology, finance and facilities related services until mid-2019, and the compensation received for such transition services is being reflected as a reduction to the underlying expenses incurred by Nasdaq to provide such transition services.

* * * * * *

2017 Acquisitions



	Purchase Consideration		Total Net Liabilities Acquired			Total Net Deferred Tax Liability			Acquired Intangible Assets		Goodwill
	(in millions)
eVestment	$	744	$	(10	)	$	(96	)	$	405	$	445

The amounts in the table above represent the final allocation of purchase price. The allocation of the purchase price was subject to revision during the measurement period, a period not to exceed 12 months from the acquisition date. Adjustments to the provisional values, which may include tax and other estimates, during the measurement period are recorded in the reporting period in which the adjustment amounts are determined. In October 2018, we recorded a measurement period adjustment related to our acquisition of eVestment which is discussed below under “Acquisition of eVestment.” The allocation of the purchase price for eVestment was finalized in October 2018.

See “Intangible Assets” below for further discussion of intangible assets acquired in the eVestment acquisition.

Acquisition of eVestment

In October 2017, we acquired eVestment for $705 million. The aggregate cash consideration of $744 million, which is net of cash acquired of $22 million, included $39 million of estimated tax benefits associated with the transaction. We acquired net liabilities, at fair value, totaling $10 million and we recorded a net deferred tax liability of $104 million, which is net of the $39 million in estimated tax benefits associated with the transaction. The deferred tax liability recorded of $143 million relates to differences in the U.S. GAAP and tax basis of our investment in eVestment. In October 2018, we recorded a measurement period adjustment of $8 million to the estimated fair value of deferred tax assets to reflect a revised assessment following the receipt of new information. The adjustment resulted in an increase to deferred tax assets recorded and a decrease to goodwill. The adjustment did not result in an impact to our Consolidated Statements of Income. eVestment is part of our Information Services segment.

Nasdaq used cash on hand and issuances of commercial paper to fund this acquisition.

Acquisition of Sybenetix

In September 2017, we acquired Sybenetix which is part of our Market Technology segment.

* * * * * *

2016 Acquisitions



	Purchase Consideration		Total Net Assets (Liabilities) Acquired			Total Net Deferred Tax Liability			Acquired Intangible Assets		Goodwill
	(in millions)
ISE	$	1,070	$	83		$	(185	)	$	623	$	549
Boardvantage	242		28			(38		)	111		141
Marketwired	111		(1		)	(5		)	31		86
Nasdaq Canada	116		6			(20		)	76		54

The amounts in the table above represent the final allocation of purchase price for each acquisition. The allocations of the purchase price were subject to revision during the measurement period, a period not to exceed 12 months from the acquisition date. Adjustments to the provisional values, which may include tax and other estimates, during the measurement period are recorded in the reporting period in which the adjustment amounts are determined. We finalized the allocation of the purchase price for Marketwired and Nasdaq Canada in February 2017. In the second quarter of 2017, we finalized the allocation of the purchase price for Boardvantage and ISE. There were no adjustments to the provisional values during the 12-month measurement period for Nasdaq Canada and ISE. In the second quarter of 2016, we recorded a measurement period adjustment of $5 million related to our acquisition of Marketwired which is discussed below under “Acquisition of Marketwired.” In the second quarter of 2017, we recorded a measurement period adjustment of $7 million related to our acquisition of Boardvantage which is discussed below under “Acquisition of Boardvantage.”

See “Intangible Assets” below for further discussion of intangible assets acquired through our 2016 acquisitions.

Acquisition of ISE

In June 2016, we acquired ISE for $1,070 million. We acquired net assets, at fair value, totaling $83 million and recorded a net deferred tax liability of $185 million, comprised of a deferred tax liability of $266 million and a deferred tax asset of $81 million, related to differences in the U.S. GAAP and tax basis of our investment in ISE. ISE is part of our Market Services, Information Services and Market Technology segments.

In May 2016, we issued the 2023 Notes and in June 2016, we issued the 2026 Notes to fund this acquisition. See “1.75% Senior Unsecured Notes,” and “3.85% Senior Unsecured Notes,” of Note 9, “Debt Obligations,” for further discussion.

Acquisition of Boardvantage

In May 2016, we acquired Boardvantage for $242 million ($197 million in cash paid plus $45 million in working capital adjustments, which primarily includes cash acquired). We acquired net assets, at fair value, totaling $28 million and recorded a net deferred tax liability of $45 million, comprised of a deferred tax liability of $46 million and a deferred tax asset of $1 million, related to differences in the U.S. GAAP and tax basis of our investment in Boardvantage. In the second quarter of 2017, we recorded a measurement period adjustment of $7 million to the estimated fair value of deferred tax assets to reflect a revised assessment following the receipt of new information. The adjustment resulted in an increase to deferred tax assets recorded and a decrease to goodwill. The adjustment did not result in an impact to our Consolidated Statements of Income. Boardvantage is part of our Corporate Solutions business within our Corporate Services segment.

Nasdaq borrowed $197 million under the revolving credit commitment of a previous credit facility to fund this acquisition.

Acquisition of Marketwired

In February 2016, we acquired Marketwired for $111 million ($109 million in cash paid plus $2 million in working capital adjustments). We acquired net liabilities, at fair value, totaling $1 million and recorded a deferred tax liability of $10 million related to differences in the U.S. GAAP and tax basis of our investment in Marketwired. In the second quarter of 2016, we recorded a measurement period adjustment of $5 million to the estimated fair value of deferred tax liabilities to reflect a revised assessment following the receipt of new information. The adjustment resulted in a decrease to both deferred tax liabilities recorded and goodwill. The adjustment did not result in an impact to our Consolidated Statements of Income. Marketwired was part of our Corporate Solutions business within our Corporate Services segment.

Nasdaq borrowed $109 million under the revolving credit commitment of a previous credit facility to fund this acquisition.

Acquisition of Nasdaq Canada

In February 2016, we acquired Nasdaq Canada for $116 million ($115 million in cash paid plus $1 million in working capital adjustments). We acquired net assets, at fair value, totaling $6 million and recorded a deferred tax liability of $20 million related to differences in the U.S. GAAP and tax basis of our investment in Nasdaq Canada. Nasdaq Canada is part of our Market Services segment and our Data Products business within our Information Services segment.

Nasdaq used cash on hand and borrowed $55 million under the revolving credit commitment of a previous credit facility to fund this acquisition.

* * * * * *

Intangible Assets

The following table presents the details of significant acquired intangible assets at the date of each acquisition. All acquired intangible assets with finite lives are amortized using the straight-line method.



	2017			2016
	eVestment			ISE			Boardvantage			Marketwired			Nasdaq Canada
	($ in millions)
Exchange registrations	$	—		$	467		$	—		$	—		$	—
Discount rate used	—			8.6		%	—			—			—
Estimated average useful life	—			Indefinite			—			—			—
Customer relationships	$	378		$	148		$	103		$	29		$	76
Discount rate used	9.3		%	9.1		%	15.5		%	16.4		%	10.3		%
Estimated average useful life	14 years			13 years			14 years			6 years			17 years
Trade name	$	13		$	8		$	2		$	2		$	—
Discount rate used	9.2		%	8.6		%	15.0		%	15.8		%	—
Estimated average useful life	8 years			Indefinite			1 year			2 years			—
Technology	$	14		$	—		$	6		$	—		$	—
Discount rate used	9.2		%	—			15.5		%	—			—
Estimated average useful life	8 years			—			5 years			—			—
Total intangible assets	$	405		$	623		$	111		$	31		$	76

Exchange Registrations

As part of our acquisition of ISE we acquired exchange registrations. The exchange registrations represent licenses that provide ISE with the ability to operate its options exchanges.

Nasdaq views these intangible assets as a perpetual license to operate the exchanges so long as ISE meets its regulatory requirements. Nasdaq selected a variation of the income approach called the Greenfield Approach to value the exchange registrations. The Greenfield Approach refers to a discounted cash flow analysis that assumes the buyer is building the exchange from a start-up business to a normalized level of operations as of the acquisition date. This discounted cash flow model considers the required resources and eventual returns from the build-out of operational exchanges and the acquisition of customers, once the exchange registrations are obtained. The advantage of this approach is that it reflects the actual expectations that will arise from an investment in the registrations and it directly values the registrations. The Greenfield Approach relies on assumptions regarding projected revenues, margins, capital expenditures, depreciation, and working capital during the 2 year pre-trade phase, the 10 year ramp-up period, as well as the terminal period.

In developing a discount rate for the exchange registrations, we estimated a weighted-average cost of capital for the overall business and we employed this rate when discounting the cash flows. The resulting discounted cash flows were then tax-effected at the applicable statutory rate.

Customer Relationships

As part of all of our 2017 and 2016 acquisitions, we acquired customer relationships. Customer relationships represent the non-contractual and contractual relationships with customers.

Methodology

For our 2017 and 2016 acquisitions, customer relationships were valued using the income approach, specifically an excess earnings method. The excess earnings method examines the economic returns contributed by the identified tangible and intangible assets of a company, and then isolates the excess return that is attributable to the intangible asset being valued.

Discount Rate

The discount rates used reflect the amount of risk associated with the hypothetical cash flows for the customer relationships relative to the overall business. In developing a discount rate for the customer relationships, we estimated a weighted-average cost of capital for the overall business and we employed this rate when discounting the cash flows. The resulting discounted cash flows were then tax-effected at the applicable statutory rate.

For our acquisitions of eVestment, Marketwired and Nasdaq Canada, a discounted tax amortization benefit was added to the fair value of the assets under the assumption that the customer relationships would be amortized for tax purposes over a period of 15 years.

Estimated Useful Life

We estimate the useful life based on the historical behavior of the customers and a parallel analysis of the customers using the excess earnings method.

Trade Names

As part of our acquisitions of eVestment and ISE, we acquired trade names. These trade names are recognized in the industry and carry a reputation for quality. As such, the reputation and positive recognition embodied in these trade names are a valuable asset to Nasdaq.

Methodology

The eVestment and ISE trade names were valued using the income approach, specifically the relief-from-royalty method, or RFRM. The RFRM is used to estimate the cost savings that accrue to the owner of an intangible asset who would otherwise have to pay royalties or license fees on revenues earned through the use of the asset. The royalty rate is applied to the projected revenue over the expected remaining life of the intangible asset to estimate royalty savings. The net after-tax royalty savings are calculated for each year in the remaining economic life of the trade name and discounted to present value.

Discount Rate

The discount rates used reflect the amount of risk associated with the hypothetical cash flows for each trade name relative to the overall business as discussed above in “Customer Relationships.”

Estimated Useful Life

We have estimated the useful life of the eVestment trade name to be 8 years and the estimated useful life of the ISE trade name to be indefinite based on the number of years the name has been in service, its popularity within the industry, and our intention to continue to use it in the branding of products.

Technology

As part of our acquisitions of eVestment and Boardvantage, we acquired developed technology.

Methodology

The developed technologies were valued using the income approach, specifically the RFRM as discussed above in “Trade Names.”

Discount Rate

The discount rates used reflect the amount of risk associated with the hypothetical cash flows for the developed technology relative to the overall business as discussed above in “Customer Relationships.”

Estimated Useful Life

We have estimated the useful life of the eVestment technology to be 8 years and the estimated useful life of the Boardvantage technology to be 5 years.

Pro Forma Results and Acquisition-related Costs

The consolidated financial statements for the years ended December 31, 2018, 2017 and 2016 include the financial results of the above 2018, 2017 and 2016 acquisitions from the date of each acquisition. Pro forma financial results have not been presented since these acquisitions both individually and in the aggregate were not material to our financial results.

Acquisition-related costs for the transactions described above were expensed as incurred and are included in merger and strategic initiatives expense in the Consolidated Statements of Income.

Assets and Liabilities Held For Sale

12 Months Ended

Dec. 31, 2018

Discontinued Operations and Disposal Groups [Abstract]

Assets and Liabilities Held For Sale

As of December 31, 2018, our BWise business was recorded as held for sale and as of December 31, 2017, our Public Relations Solutions and Digital Media Services businesses were recorded as held for sale.

2018 Assets and Liabilities Held For Sale

As part of Nasdaq's renewed corporate strategy to embrace our leading technology, information analytics and market strengths, in December 2018, we decided to sell BWise, our internal audit, regulatory compliance management, and operational risk management software that comprises our governance, risk and compliance product offering. BWise is part of our Corporate Solutions business within our Corporate Services segment.

We determined that we met all of the criteria to classify the assets and liabilities of BWise as held for sale as of December 31, 2018. The disposal of BWise did not represent a strategic shift that would have a major effect on our operations and financial results and is, therefore, not classified as discontinued operations. No impairment charge was recorded for the year ended December 31, 2018 as the carrying amount of the net assets was less than the fair value less costs to sell. Fair value was determined based upon the anticipated sales price of these products and services based on current market conditions and assumptions made by management, which may differ from actual results and may result in an impairment if market conditions deteriorate.

In February 2019, we entered into an agreement to sell BWise. Based on the sales price in the agreement, no impairment charge was recorded. See “Agreement to Sell BWise,” of Note 21, “Subsequent Events,” for further discussion.

2017 Assets and Liabilities Held For Sale

As of December 31, 2017, the Public Relations Solutions and Digital Media Services businesses were classified as held for sale. The disposal of these businesses did not represent a strategic shift that would have had a major effect on our operations and financial results and were, therefore, not classified as discontinued operations.

In April 2018, we sold these businesses. See “2018 Divestiture,” of Note 3, “Acquisitions and Divestiture,” for further discussion. Based on the sales price in the agreement, no impairment charge was recorded at the time of the sale as the carrying amount of the net assets was less than the sales price in the agreement less costs to sell.

Major Classes of Assets and Liabilities Held For Sale

The carrying amounts of the major classes of assets and liabilities that were classified as held for sale at December 31, 2018 and 2017 were as follows:



	December 31, 2018		December 31, 2017
	(in millions)
Receivables, net	$	13	$	27
Property and equipment, net	10		21
Goodwill⁽¹⁾	47		202
Intangible assets, net⁽²⁾	16		38
Other assets	3		9
Total assets held for sale⁽³⁾	$	89	$	297

Deferred tax liabilities	$	4	$	16
Deferred revenue	12		2
Other current liabilities	4		27
Total liabilities held for sale⁽⁴⁾	$	20	$	45

____________


⁽¹⁾	The assignment of goodwill was based on the relative fair value of the disposal group and the portion of the remaining reporting unit.

⁽²⁾Primarily represents customer relationships.

⁽³⁾Included in other current assets in the Consolidated Balance Sheets as of December 31, 2018 and 2017.

⁽⁴⁾Included in other current liabilities in the Consolidated Balance Sheets as of December 31, 2018 and 2017.

Goodwill and Acquired Intangible Assets

12 Months Ended

Dec. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Acquired Intangible Assets

Goodwill

The following table presents the changes in goodwill by business segment during the year ended December 31, 2018:



	Market Services			Corporate Services			Information Services			Market Technology			Total
	(in millions)
Balance at December 31, 2017	$	3,546		$	490		$	2,362		$	188		$	6,586
Goodwill acquired	—			—			56			—			56
Measurement period adjustment	—			—			(8		)	—			(8		)
Reclassification of goodwill⁽¹⁾	—			29			—			(29		)	—
Goodwill reclassified to held for sale⁽²⁾	—			(47		)	—			—			(47		)
Foreign currency translation adjustment	(116		)	(17		)	(77		)	(14		)	(224		)
Balance at December 31, 2018	$	3,430		$	455		$	2,333		$	145		$	6,363

____________

⁽¹⁾ Concurrent with the realignment of our BWise internal audit, regulatory compliance management, and operational risk management software solutions from our Market Technology segment to our Corporate Services segment, goodwill was reassigned to the Corporate Services segment using a relative fair value approach.


⁽²⁾	See Note 5, “Assets and Liabilities Held for Sale,” for further discussion.

The goodwill acquired for Information Services shown above relates to our acquisitions of Quandl and RedQuarry. See “2018 Acquisitions,” of Note 3, “Acquisitions and Divestiture,” for further discussion.

In October 2018, we recorded a measurement period adjustment of $8 million to the estimated fair value of deferred tax assets related to our acquisition of eVestment. See “Acquisition of eVestment,” of Note 3, “Acquisitions and Divestiture,” for further discussion of the adjustment.

As of December 31, 2018, the amount of goodwill that is expected to be deductible for tax purposes in future periods is $807 million.

Goodwill represents the excess of purchase price over the value assigned to the net assets, including identifiable intangible assets, of a business acquired. Goodwill is allocated to our reporting units based on the assignment of the fair values of each reporting unit of the acquired company. We test goodwill for impairment at the reporting unit level annually, or in interim periods if certain events occur indicating that the carrying amount may be impaired, such as changes in the business climate, poor indicators of operating performance or the sale or disposition of a significant portion of a reporting unit. There was no impairment of goodwill for the years ended December 31, 2018, 2017 and 2016; however, events such as extended economic weakness or unexpected significant declines in operating results of a reporting unit may result in goodwill impairment charges in the future.

* * * * * *

Acquired Intangible Assets

The following table presents details of our total acquired intangible assets, both finite- and indefinite-lived:



	December 31, 2018										December 31, 2017
	Gross Amount			Accumulated Amortization			Net Amount			Weighted-Average Useful Life (in Years)	Gross Amount			Accumulated Amortization			Net Amount			Weighted-Average Useful Life (in Years)
	(in millions)										(in millions)
Finite-Lived Intangible Assets
Technology	$	54		$	(15	)	$	39		9	$	65		$	(22	)	$	43		8
Customer relationships⁽¹⁾	1,532			(456		)	1,076			18	1,708			(526		)	1,182			18
Other	17			(2		)	15			8	17			(4		)	13			8
Foreign currency translation adjustment	(149		)	64			(85		)		(111		)	46			(65		)
Total finite-lived intangible assets	$	1,454		$	(409	)	$	1,045			$	1,679		$	(506	)	$	1,173
Indefinite-Lived Intangible Assets
Exchange and clearing registrations	$	1,257		$	—		$	1,257			$	1,257		$	—		$	1,257
Trade names	122			—			122				129			—			129
Licenses	52			—			52				52			—			52
Foreign currency translation adjustment	(176		)	—			(176		)		(143		)	—			(143		)
Total indefinite-lived intangible assets	$	1,255		$	—		$	1,255			$	1,295		$	—		$	1,295
Total intangible assets	$	2,709		$	(409	)	$	2,300			$	2,974		$	(506	)	$	2,468

____________


⁽¹⁾	The decrease in the gross amount and accumulated amortization for customer relationships as of December 31, 2018 compared with 2017 is primarily due to certain intangible assets that became fully amortized in fourth quarter of 2018.

As a result of our decision to sell BWise, we reclassified certain intangibles assets to held for sale. The following table presents the gross amount, accumulated amortization and net amount of finite-lived and indefinite-lived intangible assets that have been reclassified as assets held for sale as of December 31, 2018. See Note 5, “Assets and Liabilities Held for Sale,” for further discussion.



	Gross Amount		Accumulated Amortization			Net Amount
	(in millions)
Finite-lived intangible assets reclassified as held for sale - customer relationships	$	21	$	(10	)	$	11
Indefinite-lived intangible assets reclassified as held for sale - trade name	$	5	$	—		$	5
Total intangible assets held for sale	$	26	$	(10	)	$	16

In February 2019, we entered into an agreement to sell BWise. See “Agreement to Sell BWise,” of Note 21, “Subsequent Events,” for further discussion.

In addition, in April 2018, in connection with the sale of the Public Relations Solutions and Digital Media Services businesses, we recorded a $2 million pre-tax, non-cash write-off related to an indefinite-lived intangible asset trade name.

Amortization expense for acquired finite-lived intangible assets was $109 million for the year ended December 31, 2018, $92 million for the year ended December 31, 2017, and $82 million for the year ended December 31, 2016. Amortization expense increased in 2018 and 2017 primarily due to additional amortization expense associated with acquired intangible assets in 2017. These amounts are included in depreciation and amortization expense in the Consolidated Statements of Income.

The estimated future amortization expense (excluding the impact of foreign currency translation adjustments of $85 million as of December 31, 2018) of acquired finite-lived intangible assets as of December 31, 2018 is as follows:



	(in millions)
2019	$	100
2020	98
2021	97
2022	94
2023	92
2024 and thereafter	649
Total	$	1,130

Investments

12 Months Ended

Dec. 31, 2018

Investments, Debt and Equity Securities [Abstract]

Investments

The following table presents the details of our investments:



	December 31, 2018		December 31, 2017
	(in millions)
Trading securities	$	259	$	221
Available-for-sale investment securities	9		14
Financial investments, at fair value	$	268	$	235

Equity method investments	$	135	$	131
Equity securities	$	44	$	152

Financial Investments, at Fair Value

Trading Securities

Trading securities, which are included in financial investments, at fair value in the Consolidated Balance Sheets, are primarily comprised of highly rated European government debt securities, of which $166 million as of December 31, 2018 and $160 million as of December 31, 2017, are assets primarily utilized to meet regulatory capital requirements, mainly for our clearing operations at Nasdaq Clearing.

Available-for-Sale Investment Securities

As of December 31, 2018 and 2017, available-for-sale investment securities, which are included in financial investments, at fair value in the Consolidated Balance Sheets, were primarily comprised of commercial paper. As of December 31, 2018 and 2017, the cumulative unrealized gains and losses on these securities were immaterial.

Equity Method Investments

As of December 31, 2018 and December 31, 2017, our equity method investments primarily included equity interests in OCC and EuroCCP N.V.

The carrying amounts of our equity method investments are included in other non-current assets in the Consolidated Balance Sheets.

Net income recognized from our equity interest in the earnings and losses of these equity method investments was $18 million for the year ended December 31, 2018, $15 million for the year ended December 31, 2017, and $2 million for the year ended December 31, 2016. The change in the year ended December 31, 2018 compared with the same period in 2017 is primarily due to an increase in income recognized from our investments in OCC and EuroCCP N.V. The change in the year ended December 31, 2017 compared with the same period in 2016 relates to our additional 20.0% ownership interest in OCC, which we acquired in connection with our acquisition of ISE in June 2016, bringing our total ownership interest in OCC to 40.0%, partially offset by the write-off of an equity method investment which was offset by a gain resulting from the sale of a percentage of a separate equity method investment.

Capital Contribution to OCC

In March 2015, OCC implemented a capital plan under which the options exchanges that are OCC’s stockholders contributed $150 million of new equity capital to OCC, committed to make future replenishment capital contributions under certain circumstances, and received commitments regarding future dividend payments and related matters. See “Other Commitments,” of Note 19, “Commitments, Contingencies and Guarantees,” for further discussion of our commitment to make future replenishment capital contributions. Nasdaq PHLX and ISE each contributed $30 million of new equity capital under the OCC capital plan. OCC adopted specific policies with respect to fees, customer refunds and stockholder dividends, which envision an annual dividend equal to the portion of OCC’s after-tax income that exceeds OCC’s capital requirements after payment of refunds to OCC’s clearing members (such refunds are generally 50% of the portion of OCC’s pre-tax income that exceeds OCC’s capital requirements). In 2018, 2017 and 2016, OCC disbursed annual dividends under the capital plan and Nasdaq, via its ownership interests, as the owner of two shares, received $13 million in 2018, $10 million in 2017 and $4 million in 2016.

In February 2016, after the SEC approved the rule change establishing the OCC capital plan, certain industry participants appealed that approval in the U.S. Court of Appeals. In August 2017, the Court of Appeals remanded the case to the SEC. In February 2019, on remand from the Court of Appeals, the SEC disapproved the OCC rule change that established the capital plan. In its decision, the SEC noted that it will consider any requests for exemptive or other relief that OCC might seek while OCC considers its alternatives to ensure compliance with relevant regulations. OCC has not publicly announced its plans in light of the order. As a result of the SEC decision, OCC may return capital to us or adopt new policies, which may impact us. We are unable to predict the outcome or exact timing of resolution of this matter.

Equity Securities

The carrying amounts of our equity securities are included in other non-current assets in the Consolidated Balance Sheets. As of December 31, 2018, our equity securities primarily represent various strategic investments made through our corporate venture program. As of December 31, 2017, our equity securities primarily represented our 5.0% ownership in Borsa Istanbul and our 5.0% ownership interest in LCH.

In December 2018, we sold our 5.0% ownership interest in LCH for $169 million in cash. As a result of the sale, we recognized a pre-tax gain of $118 million ($93 million after tax). The gain is included in gain on sale of investment security in the Consolidated Statements of Income for the year ended December 31, 2018.

The Borsa Istanbul shares, which were issued to us in the first quarter of 2014, were part of the consideration received under a market technology agreement. This investment had a carrying amount of $75 million which was guaranteed to us via a put option negotiated as part of the market technology agreement. During the second quarter of 2018, we exercised the put option and we expect to receive cash consideration in installments through 2022. In 2018, we received $45 million in cash. The remaining receivable is recorded in other current assets and other non-current assets in the Consolidated Balance Sheets.

Property and Equipment, net

12 Months Ended

Dec. 31, 2018

Property, Plant and Equipment [Abstract]

Property and Equipment, net

The following table presents our major categories of property and equipment, net:



	Year Ended December 31,
	2018			2017
	(in millions)
Data processing equipment and software	$	526		$	626
Furniture, equipment and leasehold improvements	274			279
Total property and equipment	800			905
Less: accumulated depreciation and amortization	(424		)	(505		)
Total property and equipment, net	$	376		$	400

Depreciation and amortization expense for property and equipment was $101 million for the year ended December 31, 2018, $96 million for the year ended December 31, 2017 and $88 million for the year ended December 31, 2016. The increase in depreciation and amortization expense in 2018 and 2017 was primarily due to additional expense associated with assets and software placed in service. These amounts are included in depreciation and amortization expense in the Consolidated Statements of Income.

There were no impairments of property and equipment recorded in 2018. In 2017, we recorded a pre-tax, non-cash property and equipment asset impairment charge of $9 million primarily related to the write-off of capitalized software and hardware equipment associated with our 2017 and 2016 acquisitions. This charge is included in merger and strategic initiatives expense in the Consolidated Statements of Income for 2017.

As of December 31, 2018 and 2017, we did not own any real estate properties.

Deferred Revenue

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Deferred Revenue

Deferred revenue represents consideration received that is yet to be recognized as revenue. The changes in our deferred revenue during the year ended December 31, 2018 are reflected in the following table:



	Initial Listing Revenues			Annual Listings Revenues			Market Technology Revenues			Corporate Solutions and Other Revenues⁽³⁾			Information Services Revenues			Other⁽⁴⁾			Total
	(in millions)
Balance at December 31, 2017	$	64		$	3		$	109		$	37		$	40		$	34		$	287
Additions	29			236			168			242			169			23			867
Revenue recognized	(25		)	(234		)	(183		)	(242		)	(130		)	(36		)	(850		)
Reclassification of deferred revenue⁽¹⁾	—			—			(11		)	11			—			—			—
Deferred revenue reclassified to held for sale⁽²⁾	—			—			—			(12		)	—			—			(12		)
Translation adjustment	(2		)	(1		)	(8		)	—			1			(1		)	(11		)
Balance at December 31, 2018	$	66		$	4		$	75		$	36		$	80		$	20		$	281

____________


⁽¹⁾	Concurrent with the realignment of our BWise internal audit, regulatory compliance management, and operational risk management software solutions from our Market Technology segment to our Corporate Services segment, deferred revenue was reassigned to the Corporate Services segment.

⁽²⁾ See Note 5, “Assets and Liabilities Held for Sale,” for further discussion.


⁽³⁾	Other revenues include the revenues from the Public Relations Solutions and Digital Media Services businesses through the date of sale (April 2018). See “2018 Divestiture,” of Note 3, “Acquisitions and Divestiture,” to the consolidated financial statements for further discussion.


⁽⁴⁾	The balance as of December 31, 2018 and 2017 primarily includes deferred revenue from listing of additional shares fees which are included in our Listing Services segment. The activity during the period primarily pertains to our Trade Management Services and FICC businesses, which are included in our Market Services segment, for contracts paid monthly or quarterly in advance of the service.

On January 1, 2018, we adopted Topic 606. As a result, a portion of revenues that were previously deferred were recognized either in prior period revenues, through restatement, or as an adjustment to retained earnings upon adoption of the new standard. See “Revenue From Contracts With Customers,” of Note 2, “Summary of Significant Accounting Policies,” for a description of our initial listing, annual listing, market technology, corporate solutions, and information services revenues and the revenue recognition policy for each of these revenue streams.

As of December 31, 2018, we estimate that our deferred revenue will be recognized in the following years:



	Initial Listing Revenues		Annual Listings Revenues		Market Technology Revenues		Corporate Solutions Revenues		Information Services Revenues		Other⁽¹⁾		Total
	(in millions)
Fiscal year ended:
2019	$	23	$	4	$	47	$	33	$	77	$	10	$	194
2020	20		—		21		3		3		7		54
2021	10		—		7		—		—		2		19
2022	7		—		—		—		—		1		8
2023	5		—		—		—		—		—		5
2024 and thereafter	1		—		—		—		—		—		1
Total	$	66	$	4	$	75	$	36	$	80	$	20	$	281

____________


⁽¹⁾	Other primarily includes revenues from listing of additional shares fees which are included in our Listing Services business.

The timing of recognition of our deferred market technology revenues is primarily dependent upon the completion of customization and any significant modifications made pursuant to existing market technology contracts. As such, as it relates to market technology revenues, the timing represents our best estimate.

Debt Obligations

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Debt Obligations

The following table presents the changes in the carrying amount of our debt obligations during the year ended December 31, 2018:



	December 31, 2017		Additions		Payments, Accretion and Other			December 31, 2018
Short-term debt:	(in millions)
Commercial paper	$	480	$	4,096	$	(4,301	)	$	275
Senior unsecured floating rate notes due March 22, 2019⁽¹⁾	498		—		2			500
$400 million senior unsecured term loan facility due November 25, 2019 (average interest rate of 3.48% for the period January 1, 2018 through December 31, 2018)⁽²⁾	100		—		—			100
Total short-term debt	1,078		4,096		(4,299		)	875
Long-term debt:
5.55% senior unsecured notes due January 15, 2020	599		—		—			599
3.875% senior unsecured notes due June 7, 2021	716		—		(30		)	686
4.25% senior unsecured notes due June 1, 2024	496		—		1			497
1.75% senior unsecured notes due May 19, 2023	712		—		(30		)	682
3.85% senior unsecured notes due June 30, 2026	496		—		—			496
$1 billion revolving credit commitment due April 25, 2022 (average interest rate of 2.74% for the period January 1, 2018 through December 31, 2018)	110		—		(114		)	(4		)
Total long-term debt	3,129		—		(173		)	2,956
Total debt obligations	$	4,207	$	4,096	$	(4,472	)	$	3,831

____________


⁽¹⁾	Balance was reclassified to short-term debt as of March 31, 2018.


⁽²⁾	Balance was reclassified to short-term debt as of December 31, 2018.

Commercial Paper Program

Our U.S. dollar commercial paper program is supported by our 2017 Credit Facility which provides liquidity support for the repayment of commercial paper issued through the commercial paper program. See “2017 Credit Facility” below for further discussion of our 2017 Credit Facility. The effective interest rate of commercial paper issuances fluctuate as short term interest rates and demand fluctuate. The fluctuation of these rates due to market conditions may impact our interest expense.

As of December 31, 2018, commercial paper notes in the table above reflect the aggregate principal amount, less the unamortized discount which is being accreted through interest expense over the life of the applicable notes. The original maturities of these notes range from 24 days to 67 days and the weighted-average maturity is 33 days. The weighted-average effective interest rate is 3.03% per annum.

Senior Unsecured Notes

Our senior unsecured notes were all issued at a discount. As a result of the discount, the proceeds received from each issuance were less than the aggregate principal amount. As of December 31, 2018, the amounts in the table above reflect the aggregate principal amount, less the unamortized debt discount and the unamortized debt issuance costs which are being accreted through interest expense over the life of the applicable notes. Our senior unsecured notes are general unsecured obligations of ours and rank equally with all of our existing and future unsubordinated obligations and they are not guaranteed by any of our subsidiaries. The senior unsecured notes were issued under indentures that, among other things, limit our ability to consolidate, merge or sell all or substantially all of our assets, create liens, and enter into sale and leaseback transactions.

With the exception of the 2020 Notes, upon a change of control triggering event (as defined in the various note indentures), the terms require us to repurchase all or part of each holder’s notes for cash equal to 101% of the aggregate principal amount purchased plus accrued and unpaid interest, if any.

Senior Unsecured Floating Rate Notes

In September 2017, Nasdaq issued the 2019 Notes. The 2019 Notes pay interest quarterly in arrears at a rate equal to the three-month U.S. dollar LIBOR as determined at the beginning of each quarterly period plus 0.39% per annum until March 22, 2019.

As of December 31, 2018, the amount outstanding of $500 million is due upon maturity at March 22, 2019, which we expect to repay with cash on hand and proceeds from issuances of commercial paper or borrowings from our revolving credit commitment under our 2017 Credit Facility.

5.55% Senior Unsecured Notes

In January 2010, Nasdaq issued the 2020 Notes. The 2020 Notes pay interest semiannually at a rate of 5.55% per annum until January 15, 2020.

3.875% Senior Unsecured Notes

In June 2013, Nasdaq issued the 2021 Notes. The 2021 Notes pay interest annually at a rate of 3.875% per annum until June 7, 2021 and such rate may vary with Nasdaq’s debt rating up to a rate not to exceed 5.875%.

The 2021 Notes have been designated as a hedge of our net investment in certain foreign subsidiaries to mitigate the foreign exchange risk associated with certain investments in these subsidiaries. The decrease in the carrying amount of $30 million noted in the “Payments, Accretion and Other” column in the table above primarily reflects the translation of the 2021 Notes into U.S. dollars and is recorded in accumulated other comprehensive loss within stockholders’ equity in the Consolidated Balance Sheets as of December 31, 2018.

4.25% Senior Unsecured Notes

In May 2014, Nasdaq issued the 2024 Notes. The 2024 Notes pay interest semiannually at a rate of 4.25% per annum until June 1, 2024 and such rate may vary with Nasdaq’s debt rating up to a rate not to exceed 6.25%.

1.75% Senior Unsecured Notes

In May 2016, Nasdaq issued the 2023 Notes. The 2023 Notes pay interest annually at a rate of 1.75% per annum until May 19, 2023 and such rate may vary with Nasdaq’s debt rating up to a rate not to exceed 3.75%.

The 2023 Notes have been designated as a hedge of our net investment in certain foreign subsidiaries to mitigate the foreign exchange rate risk associated with certain investments in these subsidiaries. The decrease in the carrying amount of $30 million noted in the “Payments, Accretion and Other” column in the table above reflects the translation of the 2023 Notes into U.S. dollars and is recorded in accumulated other comprehensive loss within stockholders’ equity in the Consolidated Balance Sheets as of December 31, 2018.

3.85% Senior Unsecured Notes

In June 2016, Nasdaq issued the 2026 Notes. The 2026 Notes pay interest semiannually at a rate of 3.85% per annum until June 30, 2026 and such rate may vary with Nasdaq’s debt rating up to a rate not to exceed 5.85%.

Credit Facilities

As of December 31, 2018, the amounts in the table above reflect the aggregate principal amount, less the unamortized debt issuance costs which are being accreted through interest expense over the life of the applicable credit facility. Nasdaq is permitted to repay borrowings under our credit facilities at any time in whole or in part, without penalty.

Our credit facilities contain financial and operating covenants. Financial covenants include a minimum interest expense coverage ratio and a maximum leverage ratio. Operating covenants include, among other things, limitations on Nasdaq’s ability to incur additional indebtedness, grant liens on assets, dispose of assets and pay dividends. Our credit facilities allow us to pay cash dividends on our common stock. The facilities also contain customary affirmative covenants, including access to financial statements, notice of defaults and certain other material events, maintenance of properties and insurance, and events of default, including cross-defaults to our material indebtedness.

2017 Credit Facility

In April 2017, Nasdaq entered into the 2017 Credit Facility. The 2017 Credit Facility consists of a $1 billion five-year revolving credit facility (with sublimits for non-dollar borrowings, swingline borrowings and letters of credit), which replaced a former credit facility. Nasdaq intends to use funds available under the 2017 Credit Facility for general corporate purposes and to provide liquidity support for the repayment of commercial paper issued through the commercial paper program.

As of December 31, 2018, no amounts were outstanding on the 2017 Credit Facility. The $4 million balance represents unamortized debt issuance costs. Of the $1 billion that is available for borrowing, $277 million provides liquidity support for the commercial paper program and for a letter of credit. As such, as of December 31, 2018, the total remaining amount available under the 2017 Credit Facility was $723 million. See “Commercial Paper Program” above for further discussion of our commercial paper program.

Under our 2017 Credit Facility, borrowings under the revolving credit facility and swingline borrowings bear interest on the principal amount outstanding at a variable interest rate based on either the LIBOR or the base rate (as defined in the credit agreement) (or other applicable rate with respect to non-dollar borrowings), plus an applicable margin that varies with Nasdaq’s debt rating. We are charged commitment fees of 0.125% to 0.4%, depending on our credit rating, whether or not amounts have been borrowed. These commitment fees are included in interest expense and were not material for the years ended December 31, 2018, 2017 and 2016.

The 2017 Credit Facility includes an option for Nasdaq to increase the available aggregate amount by up to $500 million, subject to the consent of the lenders funding the increase and certain other conditions.

2016 Credit Facility

In March 2016, Nasdaq entered into the 2016 Credit Facility. Under our 2016 Credit Facility, borrowings bear interest on the principal amount outstanding at a variable interest rate based on either the LIBOR or the base rate (or other applicable rate with respect to non-dollar borrowings), plus an applicable margin that varies with Nasdaq’s debt rating.

As of December 31, 2018, the amount outstanding of $100 million is due upon maturity at November 25, 2019, which we expect to repay with cash on hand and proceeds from issuances of commercial paper or borrowings from our revolving credit commitment under our 2017 Credit Facility.

Other Credit Facilities

We also have credit facilities related to our Nasdaq Clearing operations in order to provide further liquidity. Credit facilities, which are available in multiple currencies, totaled $220 million as of December 31, 2018 and $187 million as of December 31, 2017 in available liquidity, none of which was utilized.

Debt Covenants

As of December 31, 2018, we were in compliance with the covenants of all of our debt obligations.

Retirement Plans

12 Months Ended

Dec. 31, 2018

Retirement Benefits [Abstract]

Retirement Plans

Defined Contribution Savings Plan

We sponsor a 401(k) Plan for U.S. employees. Employees are immediately eligible to make contributions to the plan and are also eligible for an employer contribution match at an amount equal to 100.0% of the first 6.0% of eligible employee contributions. Savings plan expense included in compensation and benefits expense in the Consolidated Statements of Income was $14 million for the year ended December 31, 2018, $13 million for 2017 and $11 million for 2016.

Pension and Supplemental Executive Retirement Plans

We maintain non-contributory, defined-benefit pension plans, non-qualified SERPs for certain senior executives and other post-retirement benefit plans for eligible employees in the U.S., collectively referred to as the Nasdaq Benefit Plans. Our pension plans and SERPs are frozen. Future service and salary for all participants do not count toward an accrual of benefits under the pension plans and SERPs. Most employees outside the U.S. are covered by local retirement plans or by applicable social laws. Benefits under social laws are generally expensed in the periods in which the costs are incurred. The total expense for these plans is included in compensation and benefits expense in the Consolidated Statements of Income and was $22 million in 2018, $21 million in 2017 and $23 million in 2016.

Nasdaq recognizes the funded status of the Nasdaq Benefit Plans, measured as the difference between the fair value of the plan assets and the benefit obligation, in the Consolidated Balance Sheets. During the third quarter of 2018, we contributed $22 million to our U.S. defined-benefit pension plans. This contribution increased the funded status of these plans to approximately 100.0%. The funded status related to the SERP was underfunded by $28 million as of December 31, 2018. As of December 31, 2017, the funded status related to the Nasdaq Benefit Plans was underfunded by $60 million and was underfunded by $59 million as of December 31, 2016. The underfunded liability for the above plans is included in accrued personnel costs and other non-current liabilities in the Consolidated Balance Sheets. The fair value of the plans' assets was $94 million as of December 31, 2018 and $79 million as of December 31, 2017 and the benefit obligation was $122 million as of December 31, 2018 and $139 million as of December 31, 2017. The plan assets of the Nasdaq Benefit Plans are invested per target allocations adopted by Nasdaq’s Pension and 401(k) Committee and are primarily invested in collective fund investments that have underlying investments in fixed income securities. The collective fund investments are valued at net asset value which is a practical expedient to estimate fair value.

Accumulated Other Comprehensive Loss

As of December 31, 2018, accumulated other comprehensive

loss for the Nasdaq Benefit Plans was $22 million reflecting an unrecognized net loss of $28 million, partially offset by an income tax benefit of $6 million, primarily due to our pension

plans.

Estimated Future Benefit Payments

We expect to make the following benefit payments to participants in the next ten fiscal years under the Nasdaq Benefit Plans:



	Pension		SERP		Post-retirement		Total
Fiscal Year Ended:	(in millions)
2019	$	4	$	2	$	—	$	6
2020	5		7		—		12
2021	4		2		—		6
2022	5		2		—		7
2023	5		2		—		7
2024 through 2028	29		10		1		40
	$	52	$	25	$	1	$	78

Share-Based Compensation

12 Months Ended

Dec. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-Based Compensation

We have a share-based compensation program for employees and non-employee directors. Share-based awards granted under this program include stock options, restricted stock (consisting of restricted stock units), and PSUs. For accounting purposes, we consider PSUs to be a form of restricted stock.

Summary of Share-Based Compensation Expense

The following table shows the total share-based compensation expense resulting from equity awards and the 15.0% discount for the ESPP for the years ended December 31, 2018, 2017 and 2016 in the Consolidated Statements of Income:



	Year Ended December 31,
	2018			2017			2016
	(in millions)
Share-based compensation expense before income taxes	$	69		$	70		$	86
Income tax benefit	(19		)	(29		)	(35		)
Share-based compensation expense after income taxes	$	50		$	41		$	51

Common Shares Available Under Our Equity Plan

As of December 31, 2018, we had approximately 11.0 million shares of common stock authorized for future issuance under our Equity Plan.

Restricted Stock

We grant restricted stock to most active employees. The grant date fair value of restricted stock awards is based on the closing stock price at the date of grant less the present value of future cash dividends. Restricted stock awards granted generally vest 25.0% on the second anniversary of the grant date, 25.0% on the third anniversary of the grant date, and 50.0% on the fourth anniversary of the grant date.

Summary of Restricted Stock Activity

The following table summarizes our restricted stock activity for the years ended December 31, 2018, 2017 and 2016:



	Restricted Stock
	Number of Awards		Weighted-Average Grant Date Fair Value

Unvested balances at December 31, 2015	3,343,738		$	35.36
Granted	724,200		$	62.91
Vested	(1,238,980	)	$	27.91
Forfeited	(268,380	)	$	43.29
Unvested balances at December 31, 2016	2,560,578		$	45.92
Granted	737,864		$	67.48
Vested	(1,102,823	)	$	38.56
Forfeited	(207,119	)	$	52.29
Unvested balances at December 31, 2017	1,988,500		$	57.34
Granted	550,544		$	81.66
Vested	(702,832	)	$	48.64
Forfeited	(252,837	)	$	63.86
Unvested balances at December 31, 2018	1,583,375		$	68.62

As of December 31, 2018, $55 million of total unrecognized compensation cost related to restricted stock is expected to be recognized over a weighted-average period of 1.8 years.

PSUs

PSUs are based on performance measures that impact the amount of shares that each recipient will receive upon vesting. We have two performance-based long-term PSU programs for certain officers, a one-year performance-based program and a three-year cumulative performance-based program that focuses on TSR.

One-Year PSU Program

The grant date fair value of PSUs under the one-year performance-based program is based on the closing stock price at the date of grant less the present value of future cash dividends. Under this program, an eligible employee receives a target grant of PSUs, but may receive from 0.0% to 150.0% of the target amount granted, depending on the achievement of performance measures. These awards vest ratably on an annual basis over a three-year period commencing with the end of the one-year performance period. Compensation cost is recognized over the performance period and the three-year vesting period based on the probability that such performance measures will be achieved, taking into account an estimated forfeiture rate.

During 2018, certain grants of PSUs with a one-year performance period exceeded the applicable performance parameters. As a result, an additional 51,914 units above target were considered granted in the first quarter of 2019.

Three-Year PSU Program

Under the three-year performance-based program, each eligible individual receives PSUs, subject to market conditions, with a three-year cumulative performance period that vest at the end of the performance period. Compensation cost is recognized over the three-year vesting period, taking into account an estimated forfeiture rate, regardless of whether the market condition is satisfied, provided that the requisite service period has been completed. Performance will be determined by comparing Nasdaq’s TSR to two peer groups, each weighted 50.0%. The first peer group consists of exchange companies, and the second peer group consists of all companies in the S&P 500. Nasdaq’s relative performance ranking against each of these groups will determine the final number of shares delivered to each individual under the program. The payout under this program will be between 0.0% and 200.0% of the number of PSUs granted and will be determined by Nasdaq’s overall performance against both peer groups. However, if Nasdaq’s TSR is negative for the three-year performance period, regardless of TSR ranking, the payout will not exceed 100.0% of the number of PSUs granted. We estimate the fair value of PSUs granted under the three-year PSU program using the Monte Carlo simulation model, as these awards contain a market condition.

Certain grants of PSUs that were issued in 2016 with a three-year performance period exceeded the applicable performance parameters. As a result, an additional 99,622 units above target were considered granted in the first quarter of 2019.

The following weighted-average assumptions were used to determine the weighted-average fair values of the PSU awards granted under the three-year PSU program:



	Year Ended December 31,
	2018		2017
Weighted-average risk free interest rate⁽¹⁾	2.36	%	1.44	%
Expected volatility⁽²⁾	18.7	%	19.2	%
Weighted-average grant date share price	$86.24		$69.45
Weighted-average fair value at grant date	$116.86		$81.57

____________


⁽¹⁾	The risk-free interest rate for periods within the expected life of the award is based on the U.S. Treasury yield curve in effect at the time of grant.


⁽²⁾	We use historic volatility for PSU awards issued under the three-year PSU program, as implied volatility data could not be obtained for all the companies in the peer groups used for relative performance measurement within the program.

In addition, the annual dividend assumption utilized in the Monte Carlo simulation model is based on Nasdaq’s dividend yield at the date of grant.

Summary of PSU Activity

The following table summarizes our PSU activity for the years ended December 31, 2018, 2017 and 2016:



	PSUs
	One-Year Program				Three-Year Program
	Number of Awards		Weighted-Average Grant Date Fair Value		Number of Awards		Weighted-Average Grant Date Fair Value
Unvested balances at December 31, 2015	423,967		$	41.34	1,439,718		$	49.41
Granted⁽¹⁾	242,642		$	58.33	761,501		$	66.89
Vested	(242,793	)	$	39.63	(879,926	)	$	43.81
Forfeited	(45,050	)	$	47.72	(6,625	)	$	69.11
Unvested balances at December 31, 2016	378,766		$	52.55	1,314,668		$	63.18
Granted⁽¹⁾	197,075		$	65.51	803,712		$	55.57
Vested	(202,073	)	$	49.93	(1,079,925	)	$	42.83
Forfeited	(40,764	)	$	55.92	(28,497	)	$	87.86
Unvested balances at December 31, 2017	333,004		$	61.39	1,009,958		$	78.18
Granted⁽¹⁾	177,831		$	80.97	484,075		$	90.92
Vested	(170,257	)	$	58.49	(655,204	)	$	64.08
Forfeited	(26,347	)	$	61.83	(1,079	)	$	81.57
Unvested balances at December 31, 2018	314,231		$	74.01	837,750		$	96.57

____________


⁽¹⁾	Includes target awards granted and certain additional awards granted based on overachievement of performance parameters.

As of December 31, 2018, $14 million of total unrecognized compensation cost related to the one-year PSU program is expected to be recognized over a weighted-average period of 1.6 years. For the three-year PSU program, $28 million of total unrecognized compensation cost is expected to be recognized over a weighted-average period of 1.4 years.

Stock Options

In January 2017, our CEO received 268,817 performance-based non-qualified stock options which will vest annually over a three-year period, with each vesting contingent upon the achievement of annual performance parameters. On January 29, 2019, Nasdaq's management compensation committee and board of directors determined that the performance goal for 2018 was met, resulting in the settlement of the second one-third of the grant. There were no stock option awards granted during the years ended December 31, 2018 and 2016.

The weighted-average grant date fair value was $66.68. We estimated the fair value of this stock option award using the Black-Scholes valuation model using the following assumptions:



Expected life (in years)	6
Weighted-average risk free interest rate	2.1	%
Expected volatility	25.6	%
Dividend yield	1.92	%

Our computation of expected life was based on an estimate of the average length of time between option grant and exercise. The interest rate for periods within the expected life of the award was based on the U.S. Treasury yield curve in effect at the time of grant. Our computation of expected volatility was an estimate of the future upward/downward fluctuations in the underlying share price. We used Nasdaq's historical volatility for the trailing 6-year period as of the grant date. Our computation of dividend yield was based on annualized dividends expressed as a percentage of share price.

Summary of Stock Option Activity

A summary of stock option activity for the years ended December 31, 2018, 2017 and 2016 is as follows:



	Number of Stock Options		Weighted-Average Exercise Price

Outstanding at December 31, 2015	2,626,487		$	27.74
Exercised	(1,219,820	)	34.00
Forfeited	(296	)	23.31
Outstanding at December 31, 2016	1,406,371		$	22.32
Granted	268,817		66.68
Exercised	(1,102,830	)	21.98
Forfeited	(978	)	21.33
Outstanding at December 31, 2017	571,380		$	43.84
Exercised	(118,094	)	24.44
Forfeited	(5,570	)	25.29
Outstanding at December 31, 2018	447,716		$	49.19
Exercisable at December 31, 2018	268,504		$	37.51

We received net cash proceeds of $3 million from the exercise of 118,094 stock options for the year ended December 31, 2018, received net cash proceeds of $24 million from the exercise of 1,102,830 stock options for the year ended December 31, 2017, and received net cash proceeds of $41 million from the exercise of 1,219,820 stock options for the year ended December 31, 2016.

The following table summarizes significant ranges of outstanding and exercisable stock options as of December 31, 2018:



					Outstanding						Exercisable
Range of Exercise Prices					Number of Stock Options	Weighted-Average Remaining Contractual Term (in years)	Weighted-Average Exercise Price		Aggregate Intrinsic Value (in millions)		Number Exercisable	Weighted-Average Remaining Contractual Term (in years)	Weighted-Average Exercise Price		Aggregate Intrinsic Value (in millions)
$	18.67	-	$	20.10	76,844	1.17	$	19.74	$	5	76,844	1.17	$	19.74	$	5
$	25.28	-	$	66.68	370,872	6.42	55.29		10		191,660	4.94	44.64		7
Total					447,716	5.52	$	49.19	$	15	268,504	3.86	$	37.51	$	12

The aggregate intrinsic value in the above table represents the total pre-tax intrinsic value (i.e., the difference between our closing stock price on December 31, 2018 of $81.57 and the exercise price, times the number of shares) based on stock options with an exercise price less than Nasdaq’s closing price of $81.57 as of December 31, 2018, which would have been received by the option holders had the option holders exercised their stock options on that date. This amount can change based on the fair market value of our common stock. The total number of in-the-money stock options exercisable as of December 31, 2018 was 0.3 million and the weighted-average exercise price was $37.51. As of December 31, 2017, 0.3 million outstanding stock options were exercisable and the weighted-average exercise price was $23.55.

The total pre-tax intrinsic value of stock options exercised was $7 million during 2018, $54 million during 2017 and $40 million during 2016.

ESPP

We have an ESPP under which approximately 1.9 million shares of our common stock have been reserved for future issuance as of December 31, 2018. Under our ESPP, employees may purchase shares having a value not exceeding 10.0% of their annual compensation, subject to applicable annual Internal Revenue Service limitations. We record compensation expense related to the 15.0% discount that is given to our employees. The following table summarizes employee activity and expenses associated with the ESPP for the years ended December 31, 2018, 2017 and 2016.



	Year Ended December 31,
	2018		2017		2016
Number of shares purchased by employees	205,785		235,859		233,464
Weighted-average price of shares purchased	$	66.79	$	58.26	$	50.39
Compensation expenses	$	3	$	3	$	4

Nasdaq Stockholders’ Equity

12 Months Ended

Dec. 31, 2018

Equity [Abstract]

Nasdaq Stockholders' Equity

Nasdaq Stockholders’ Equity

Common Stock

As of December 31, 2018, 300,000,000 shares of our common stock were authorized, 170,709,425 shares were issued and 165,165,104 shares were outstanding. The holders of common stock are entitled to one vote per share, except that our certificate of incorporation limits the ability of any person to vote in excess of 5.0% of the then-outstanding shares of Nasdaq common stock.

Common Stock in Treasury, at Cost

We account for the purchase of treasury stock under the cost method with the shares of stock repurchased reflected as a reduction to Nasdaq stockholders’ equity and included in common stock in treasury, at cost in the Consolidated Balance Sheets. Shares repurchased under our share repurchase program are currently retired and canceled. When treasury shares are reissued, they are recorded at the average cost of the treasury shares acquired. We held 5,544,321 shares of common stock in treasury as of December 31, 2018 and 4,932,402 shares as of December 31, 2017, most of which are related to shares of our common stock repurchased for the settlement of employee tax withholding obligations arising from the vesting of restricted stock and PSUs.

Share Repurchase Program

In January 2018, our board of directors authorized an additional $500 million for the share repurchase program bringing the total capacity to $726 million.

These purchases may be made from time to time at prevailing market prices in open market purchases, privately-negotiated transactions, block purchase techniques or otherwise, as determined by our management. The purchases are primarily funded from existing cash balances. The share repurchase program may be suspended, modified or discontinued at any time. The share repurchase program has no defined expiration date.

A summary of our share repurchase activity, reported based on settlement date is as follows:



	Year Ended December 31,
	2018		2017

Number of shares of common stock repurchased	4,508,426		2,843,519
Average price paid per share	$	87.43	$	71.56
Total purchase price (in millions)	$	394	$	203

As discussed above in “Common Stock in Treasury, at Cost,” shares repurchased under our share repurchase program are currently retired and cancelled. As of December 31, 2018, the remaining amount authorized for share repurchases under the program was $332 million.

Other Repurchases of Common Stock

For the year ended December 31, 2018, we repurchased 611,919 shares of our common stock in settlement of employee tax withholding obligations arising from the vesting of restricted stock.

Preferred Stock

Our certificate of incorporation authorizes the issuance of 30,000,000 shares of preferred stock, par value $0.01 per share, issuable from time to time in one or more series. As of December 31, 2018 and December 31, 2017, no shares of preferred stock were issued or outstanding.

* * * * * *

Cash Dividends on Common Stock

During 2018, our board of directors declared the following cash dividends:



Declaration Date	Dividend Per Common Share		Record Date	Total Amount Paid		Payment Date
				(in millions)
January 30, 2018	$	0.38	March 16, 2018	$	63	March 30, 2018
March 26, 2018	0.44		June 15, 2018	73		June 29, 2018
July 24, 2018	0.44		September 14, 2018	72		September 28, 2018
October 24, 2018	0.44		December 14, 2018	72		December 28, 2018
				$	280

The total amount paid of $280 million was recorded in retained earnings in the Consolidated Balance Sheets at December 31, 2018.

In March 2018, the board of directors approved a regular quarterly cash dividend of $0.44 per share on our outstanding common stock which reflects a 16.0% increase from our prior quarterly cash dividend of $0.38.

In January 2019, the board of directors declared a regular quarterly cash dividend of $0.44 per share on our outstanding common stock. The dividend is payable on March 29, 2019 to shareholders of record at the close of business on March 15, 2019. The estimated amount of this dividend is $73 million. Future declarations of quarterly dividends and the establishment of future record and payment dates are subject to approval by the board of directors.

Our board of directors maintains a dividend policy with the intention to provide stockholders with regular and growing dividends over the long term as earnings and cash flow grow.

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

The following tables present our financial assets and financial liabilities that are measured at fair value on a recurring basis as of December 31, 2018 and December 31, 2017. We did not have any financial liabilities measured at fair value on a recurring basis as of December 31, 2017.



	December 31, 2018
	Total		Level 1		Level 2		Level 3
	(in millions)
Assets at Fair Value
Financial investments, at fair value	$	268	$	133	$	135	$	—
Default fund and margin deposit investments	1,649		327		1,322		—
Total Assets at Fair Value	$	1,917	$	460	$	1,457	$	—
Liabilities at Fair Value
Other financial instruments	$	112	$	—	$	112	$	—
Total Liabilities at Fair Value	$	112	$	—	$	112	$	—



	December 31, 2017
	Total		Level 1		Level 2		Level 3
	(in millions)
Assets at Fair Value
Financial investments, at fair value	$	235	$	135	$	100	$	—
Default fund and margin deposit investments	2,129		371		1,758		—
Total Assets at Fair Value	$	2,364	$	506	$	1,858	$	—

As of December 31, 2018 and December 31, 2017, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. As of December 31, 2018 and December 31, 2017, Level 2 financial investments, at fair value were primarily comprised of trading securities, mainly corporate bonds and European mortgage bonds. Of the Level 1 and Level 2 financial investments, at fair value, $166 million as of December 31, 2018 and $160 million as of December 31, 2017 are assets primarily utilized to meet regulatory capital requirements, mainly for our clearing operations at Nasdaq Clearing.

Our Level 1 default fund and margin deposit investments were primarily comprised of highly rated European and U.S. government debt securities. Level 2 default fund and margin deposit investments were primarily comprised of central bank certificates and reverse repurchase agreements, as of December 31, 2018 and December 31, 2017.

Our Level 2 other financial instruments include a liability associated with Nasdaq Clearing's requirement to fulfill the settlement of certain contracts of a defaulted member. As of December 31, 2018, the fair value of this guarantee was $112 million and is included in other current liabilities in the Consolidated Balance Sheets. Collateral of $112 million was recorded in other current assets which offsets this liability. See Note 15, “Clearing Operations,” for further discussion of default fund contributions and margin deposits.

Financial Instruments Not Measured at Fair Value on a Recurring Basis

Some of our financial instruments are not measured at fair value on a recurring basis but are recorded at amounts that approximate fair value due to their liquid or short-term nature. Such financial assets and financial liabilities include: cash and cash equivalents, restricted cash, receivables, net, certain other current assets, accounts payable and accrued expenses, Section 31 fees payable to SEC, accrued personnel costs, commercial paper and certain other current liabilities.

Our investments in OCC and EuroCCP N.V. are accounted for under the equity method of accounting. See “Equity Method Investments,” of Note 2, “Summary of Significant Accounting Policies,” and “Equity Method Investments,” of Note 6, “Investments,” for further discussion.

We also consider our debt obligations to be financial instruments. The fair value of our debt obligations, utilizing discounted cash flow analyses for our floating rate debt and prevailing market rates for our fixed rate debt, was $3.9 billion as of December 31, 2018 and $4.4 billion as of December 31, 2017. The discounted cash flow analyses are based on borrowing rates currently available to us for debt with similar terms and maturities. The fair value of our commercial paper approximates the carrying value since the rates of interest on this short-term debt approximate market rates as of December 31, 2018. Our commercial paper and our fixed rate and floating rate debt are categorized as Level 2 in the fair value hierarchy.

For further discussion of our debt obligations, see Note 9, “Debt Obligations.”

Non-Financial Assets Measured at Fair Value on a Non-Recurring Basis

Our non-financial assets, which include goodwill, intangible assets, and other long-lived assets, are not required to be carried at fair value on a recurring basis. Fair value measures of non-financial assets are primarily used in the impairment analysis of these assets. Any resulting asset impairment would require that the non-financial asset be recorded at its fair value. Nasdaq uses Level 3 inputs to measure the fair value of the above assets on a non-recurring basis. As of December 31, 2018 and December 31, 2017, there were no non-financial assets measured at fair value on a non-recurring basis.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Clearing Operations

12 Months Ended

Dec. 31, 2018

Due to and from Broker-Dealers and Clearing Organizations [Abstract]

Clearing Operations

Nasdaq Clearing

Nasdaq Clearing is authorized and supervised under EMIR as a multi-asset clearinghouse by the SFSA. Such authorization is effective for all member states of the European Union and certain other non-member states that are part of the European Economic Area, including Norway. The clearinghouse acts as the CCP for exchange and OTC trades in equity derivatives, fixed income derivatives, resale and repurchase contracts, power derivatives, emission allowance derivatives, fuel oil derivatives, and seafood derivatives.

Through our clearing operations in the financial markets, which include the resale and repurchase market, the commodities markets, and the seafood market, Nasdaq Clearing is the legal counterparty for, and guarantees the fulfillment of, each contract cleared. These contracts are not used by Nasdaq Clearing for the purpose of trading on its own behalf. As the legal counterparty of each transaction, Nasdaq Clearing bears the counterparty risk between the purchaser and seller in the contract. In its guarantor role, Nasdaq Clearing has precisely equal and offsetting claims to and from clearing members on opposite sides of each contract, standing as the CCP on every contract cleared. In accordance with the rules and regulations of Nasdaq Clearing, default fund and margin collateral requirements are calculated for each clearing member’s positions in accounts with the CCP. See “Default Fund Contributions and Margin Deposits” below for further discussion of Nasdaq Clearing’s default fund and margin requirements.

Nasdaq Clearing maintains four member sponsored default funds: one related to financial markets, one related to commodities markets, one related to the seafood market, and a mutualized fund. Under this structure, Nasdaq Clearing and its clearing members must contribute to the total regulatory capital related to the clearing operations of Nasdaq Clearing. This structure applies an initial separation of default fund contributions for the financial, commodities and seafood markets in order to create a buffer for each market’s counterparty risks. Simultaneously, a mutualized default fund provides capital efficiencies to Nasdaq Clearing’s members with regard to total regulatory capital required. See “Default Fund Contributions” below for further discussion of Nasdaq Clearing’s default fund. Power of assessment and a liability waterfall also have been implemented. See “Power of Assessment” and “Liability Waterfall” below for further discussion. These requirements ensure the alignment of risk between Nasdaq Clearing and its clearing members.

Nasdaq Commodities Clearing Default

In September 2018, a member of the Nasdaq Clearing commodities market defaulted due to inability to post sufficient collateral to cover increased margin requirements for the positions of the relevant member, which had experienced losses due to sharp adverse movements in the Nordic - German power market spread. Nasdaq Clearing followed default procedures and offset the future market risk on the defaulting member’s positions. The default resulted in a loss of $133 million which was allocated to Nasdaq Clearing and the members of the commodities default fund in accordance with the liability waterfall as follows:


•	the first $8 million of the loss was allocated to Nasdaq Clearing’s junior capital; and


•	the remainder was allocated on a pro-rata basis to the commodities clearing members’ default funds.

During September 2018, Nasdaq Clearing replenished the utilized junior capital of $8 million for the commodities market and the commodities clearing members replenished their pro rata portions of the default fund. Nasdaq Clearing has also increased its junior capital by $14 million for the commodity market.

In November 2018, the defaulting member entered into an agreement for a consensual arrangement with creditors, including Nasdaq Clearing, for the recovery of the members’ default fund losses. Any funds recovered will be apportioned to the commodities default fund participants first and thereafter to Nasdaq Clearing in accordance with the default fund rules.

In order to reduce the risk profile of commodities clearing operations, Nasdaq Clearing has increased margin levels by increasing the confidence level on commodity products and thereby shifted the risk from waterfall resources more to each portfolio holder's collateral. In addition, Nasdaq Clearing has launched a risk management enhancement program entailing a range of risk mitigating actions, which commenced in the fourth quarter of 2018 and will continue during 2019.

In December 2018, we recorded a $23 million charge associated with the clearing default as a result of our initiating a capital relief program. The capital relief program is a voluntary program open to each commodities default fund participant; each such participant who agrees to the capital relief program will receive a proportion of the funds made available under the capital relief program as reflects their proportionate share of the aggregate of the clearing members' default fund replenishments. The capital relief program is in addition to any funds to be recovered from the defaulting member. This charge is recorded in general, administrative and other expense in the Consolidated Statements of Income for 2018.

As a result of the default, a $112 million liability was recorded in other current liabilities and $112 million of collateral was recorded in other current assets in the Consolidated Balance Sheets as of December 31, 2018 in order to allow Nasdaq Clearing to fulfill the settlement of certain contracts of the defaulted member arising from the default management process. We have established mitigating positions. The collateral and liability were previously included in Default Funds and Margin Deposits.

Default Fund Contributions and Margin Deposits

As of December 31, 2018, clearing member default fund contributions and margin deposits were as follows:



	December 31, 2018
	Cash Contributions		Non-Cash Contributions		Total Contributions
	(in millions)
Default fund contributions	$	370	$	129	$	499
Margin deposits	4,372		3,073		7,445
Total	$	4,742	$	3,202	$	7,944

In accordance with its investment policy, of the total cash contributions of $4,742 million, Nasdaq Clearing has invested $1,483 million in highly rated European and U.S. government debt securities or central bank certificates with maturity dates primarily 90 days or less and $166 million in reverse repurchase agreements secured with highly rated government securities with maturity dates that range from 4 days to 17 days. The carrying value of these securities approximates their fair value due to the short-term nature of the instruments and reverse repurchase agreements. The remainder of this balance was held in cash in demand deposit accounts at central banks and large, highly rated financial institutions. Of the total default fund contributions of $499 million, Nasdaq Clearing can utilize $436 million as capital resources in the event of a counterparty default. The remaining balance of $63 million pertains to member posted surplus balances.

In the investment activity related to default fund and margin contributions, we are exposed to counterparty risk related to reverse repurchase agreement transactions, which reflect the risk that the counterparty might become insolvent and, thus, fail to meet its obligations to Nasdaq Clearing. We mitigate this risk by only engaging in transactions with high credit quality reverse repurchase agreement counterparties and by limiting the acceptable collateral under the reverse repurchase agreement to high quality issuers, primarily government securities and other securities explicitly guaranteed by a government. The value of the underlying security is monitored during the lifetime of the contract and in the event the market value of the underlying security falls below the reverse repurchase amount our clearinghouse may require additional collateral or a reset of the contract.

Default Fund Contributions

Required contributions to the default funds are proportional to the exposures of each clearing member. When a clearing member is active in more than one market, contributions must be made to all markets’ default funds in which the member is active. Clearing members’ eligible contributions may include cash and non-cash contributions. Cash contributions received are held in cash or invested by Nasdaq Clearing, in accordance with its investment policy, either in highly rated government debt securities, time deposits, central bank certificates or reverse repurchase agreements with highly rated government debt securities as collateral. Nasdaq Clearing maintains and manages all cash deposits related to margin collateral. All risks and rewards of collateral ownership, including interest, belong to Nasdaq Clearing. Clearing members’ cash contributions are included in default funds and margin deposits in the Consolidated Balance Sheets as both a current asset and a current liability. Non-cash contributions include highly rated government debt securities that must meet specific criteria approved by Nasdaq Clearing. Non-cash contributions are pledged assets that are not recorded in the Consolidated Balance Sheets as Nasdaq Clearing does not take legal ownership of these assets and the risks and rewards remain with the clearing members. These balances may fluctuate over time due to changes in the amount of deposits required and whether members choose to provide cash or non-cash contributions. Assets pledged are held at a nominee account in Nasdaq Clearing’s name for the benefit of the clearing members and are immediately accessible by Nasdaq Clearing in the event of a default. In addition to clearing members’ required contributions to the liability waterfall, Nasdaq Clearing is also required to contribute capital to the liability waterfall and overall regulatory capital as specified under its clearinghouse rules. As of December 31, 2018, Nasdaq Clearing committed capital totaling $121 million to the liability waterfall and overall regulatory capital, in the form of government debt securities, which are recorded as financial investments, at fair value in the Consolidated Balance Sheets. The combined regulatory capital of the clearing members and Nasdaq Clearing will serve to secure the obligations of a clearing member exceeding such member’s own margin and default fund deposits and may be used to cover losses sustained by a clearing member in the event of a default.

Margin Deposits

Nasdaq Clearing requires all clearing members to provide collateral, which may consist of cash and non-cash contributions, to guarantee performance on the clearing members’ open positions, or initial margin. In addition, clearing members must also provide collateral to cover the daily margin call if needed. See “Default Fund Contributions” above for further discussion of cash and non-cash contributions.

Similar to default fund contributions, Nasdaq Clearing maintains and manages all cash deposits related to margin collateral. All risks and rewards of collateral ownership, including interest, belong to Nasdaq Clearing and are recorded in revenues. These cash deposits are recorded in default funds and margin deposits in the Consolidated Balance Sheets as both a current asset and a current liability. Pledged margin collateral is not recorded in our Consolidated Balance Sheets as all risks and rewards of collateral ownership, including interest, belong to the counterparty. Assets pledged are held at a nominee account in Nasdaq Clearing’s name for the benefit of the clearing members and are immediately accessible by Nasdaq Clearing in the event of a default.

Nasdaq Clearing marks to market all outstanding contracts and requires payment from clearing members whose positions have lost value. The mark-to-market process helps identify any clearing members that may not be able to satisfy their financial obligations in a timely manner allowing Nasdaq Clearing the ability to mitigate the risk of a clearing member defaulting due to exceptionally large losses. In the event of a default, Nasdaq Clearing can access the defaulting member’s margin and default fund deposits to cover the defaulting member’s losses.

Regulatory Capital and Risk Management Calculations

Nasdaq Clearing manages risk through a comprehensive counterparty risk management framework, which is comprised of policies, procedures, standards and financial resources. The level of regulatory capital is determined in accordance with Nasdaq Clearing’s regulatory capital policy, as approved by the SFSA. Regulatory capital calculations are continuously updated through a proprietary capital-at-risk calculation model that establishes the appropriate level of capital.

As mentioned above, Nasdaq Clearing is the legal counterparty for each contract cleared and thereby guarantees the fulfillment of each contract. Nasdaq Clearing accounts for this guarantee as a performance guarantee. We determine the fair value of the performance guarantee by considering daily settlement of contracts and other margining and default fund requirements, the risk management program, historical evidence of default payments, and the estimated probability of potential default payouts. The calculation is determined using proprietary risk management software that simulates gains and losses based on historical market prices, extreme but plausible market scenarios, volatility and other factors present at that point in time for those particular unsettled contracts. Based on this analysis, excluding any liability related to the Nasdaq commodities clearing default (see discussion above), the estimated liability was nominal and no liability was recorded as of December 31, 2018.

Power of Assessment

To further strengthen the contingent financial resources of the clearinghouse, Nasdaq Clearing has power of assessment that provides the ability to collect additional funds from its clearing members to cover a defaulting member’s remaining obligations up to the limits established under the terms of the clearinghouse rules. The power of assessment corresponds to 100.0% of the clearing member’s aggregate contribution to the financial, commodities and seafood markets’ default funds.

Liability Waterfall

The liability waterfall is the priority order in which the capital resources would be utilized in the event of a default where the defaulting clearing member’s collateral would not be sufficient to cover the cost to settle its portfolio. If a default occurs and the defaulting clearing member’s collateral, including cash deposits and pledged assets, is depleted, then capital is utilized in the following amount and order:


•	junior capital contributed by Nasdaq Clearing, which totaled $31 million as of December 31, 2018;


•	a loss sharing pool related only to the financial market that is contributed to by clearing members and only applies if the defaulting member’s portfolio includes interest rate swap products;


•	specific market default fund where the loss occurred (i.e., the financial, commodities, or seafood market), which includes capital contributions of the clearing members on a pro-rata basis;


•	senior capital contributed to each specific market by Nasdaq Clearing, calculated in accordance with clearinghouse rules, which totaled $23 million as of December 31, 2018; and


•	mutualized default fund, which includes capital contributions of the clearing members on a pro-rata basis.

If additional funds are needed after utilization of the liability waterfall, then Nasdaq Clearing will utilize its power of assessment and additional capital contributions will be required by non-defaulting members up to the limits established under the terms of the clearinghouse rules.

In addition to the capital held to withstand counterparty defaults described above, Nasdaq Clearing also has committed capital of $67 million to ensure that it can handle an orderly wind-down of its operation, and that it is adequately protected against investment, operational, legal, and business risks.

Market Value of Derivative Contracts Outstanding

The following table includes the market value of derivative contracts outstanding prior to netting:



	December 31, 2018
	(in millions)
Commodity and seafood options, futures and forwards^(1)(2)(3)	$	1,196
Fixed-income options and futures⁽¹⁾⁽²⁾	600
Stock options and futures⁽¹⁾⁽²⁾	271
Index options and futures⁽¹⁾⁽²⁾	135
Total	$	2,202

____________


⁽¹⁾	We determined the fair value of our option contracts using standard valuation models that were based on market-based observable inputs including implied volatility, interest rates and the spot price of the underlying instrument.


⁽²⁾	We determined the fair value of our futures contracts based upon quoted market prices and average quoted market yields.


⁽³⁾	We determined the fair value of our forward contracts using standard valuation models that were based on market-based observable inputs including LIBOR rates and the spot price of the underlying instrument.

Derivative Contracts Cleared

The following table includes the total number of derivative contracts cleared through Nasdaq Clearing for the years ended December 31, 2018 and 2017:



	December 31, 2018	December 31, 2017
Commodity and seafood options, futures and forwards⁽¹⁾	1,649,912	2,824,188
Fixed-income options and futures	22,839,794	20,376,383
Stock options and futures	24,978,684	26,023,816
Index options and futures	49,038,297	44,928,284
Total	98,506,687	94,152,671

____________


(1)	The total volume in cleared power related to commodity contracts was 1,067 Terawatt hours (TWh) for the year ended December 31, 2018 and 1,199 TWh for the year ended December 31, 2017.

The outstanding contract value of resale and repurchase agreements was $0.5 billion as of December 31, 2018 and $2.3 billion as of December 31, 2017. The total number of contracts cleared was 9,223,246 for the year ended December 31, 2018 and was 8,534,986 for the year ended December 31, 2017.

Leases

12 Months Ended

Dec. 31, 2018

Leases [Abstract]

Leases

We lease some of our office space under non-cancelable operating leases with third parties and sublease office space to third parties. Some of our lease agreements contain renewal options and escalation clauses based on increases in property taxes and building operating costs.

As of December 31, 2018, future minimum lease payments under non-cancelable operating leases (net of sublease income) are as follows:



	Gross Lease Commitments		Sublease Income		Net Lease Commitments
	(in millions)
Year ending December 31:
2019	$	80	$	5	$	75
2020	74		5		69
2021	66		4		62
2022	48		4		44
2023	45		3		42
Thereafter	347		2		345
Total future minimum lease payments	$	660	$	23	$	637

Rent expense for operating leases (net of sublease income of $5 million in 2018, $3 million in 2017, and $4 million in 2016) was $82 million in 2018, $83 million in 2017, and $78 million in 2016.

In February 2016, the FASB issued ASU 2016-02, “Leases.” We adopted this new guidance on January 1, 2019. See “Leases,” of “Recent Accounting Pronouncements,” of Note 2, “Summary of Significant Accounting Policies,” for further discussion.

Income Taxes

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Income Taxes

Income Before Income Tax Provision

The following table presents the domestic and foreign components of income (loss) before income tax provision:



	Year Ended December 31,
	2018		2017		2016
	(in millions)
Domestic	$	636	$	556	$	(153	)
Foreign	428		316		286
Income before income tax provision	$	1,064	$	872	$	133

Income Tax Provision

The income tax provision consists of the following amounts:



	Year Ended December 31,
	2018		2017			2016
Current income tax provision:	(in millions)
Federal	$	103	$	51		$	37
State	56		17			21
Foreign	146		68			106
Total current income tax provision	305		136			164
Deferred income tax provision (benefit):
Federal	185		(16		)	(98		)
State	116		24			(35		)
Foreign	—		(1		)	(4		)
Total deferred income provision (benefit)	301		7			(137		)
Total income tax provision	$	606	$	143		$	27

We have determined that undistributed earnings of certain non-U.S. subsidiaries will be reinvested for an indefinite period of time. We have both the intent and ability to indefinitely reinvest these earnings. As of December 31, 2018, the cumulative amount of undistributed earnings in these subsidiaries is $387 million. Given our intent to reinvest these earnings for an indefinite period of time, we have not accrued a deferred tax liability on these earnings. A determination of an unrecognized deferred tax liability related to these earnings is not practicable.

A reconciliation of the income tax provision, based on the U.S. federal statutory rate, to our actual income tax provision for the years ended December 31, 2018, 2017 and 2016 is as follows:



	Year Ended December 31,
	2018		2017		2016
Federal income tax provision at the statutory rate	21.0	%	35.0	%	35.0	%
State income tax provision, net of federal effect	3.7	%	2.6	%	(6.7	)%
Change in deferred taxes due to change in law	27.0	%	(9.9	)%	(1.2	)%
Excess tax benefits related to employee share-based compensation	(0.7	)%	(4.0	)%	—	%
Non-U.S. subsidiary earnings	0.1	%	(6.0	)%	(7.3	)%
Tax credits and deductions	(0.2	)%	(1.0	)%	(5.1	)%
Change in unrecognized tax benefits	4.7	%	(0.8	)%	4.2	%
Other, net	1.4	%	0.5	%	1.4	%
Actual income tax provision	57.0	%	16.4	%	20.3	%

The majority of the increase in our effective tax rate in 2018 compared to 2017 and the decrease in our effective tax rate in 2017 compared to 2016 was the result of the final and provisional impacts from The Tax Cuts and Jobs Act which was enacted on December 22, 2017. See “Tax Cuts and Jobs Act” below for further discussion of the impacts of this legislation on our financial statements. Also impacting the increase in the effective tax rate in 2018 compared to 2017 was the reversal of certain Swedish tax benefits recorded in prior periods and the tax expense associated with the sale of the Public Relations Solutions and Digital Media Services businesses.

We recorded income tax benefits of $9 million in 2018, $40 million in 2017 and $41 million in 2016, primarily related to share-based compensation. In 2018 and 2017, the benefit was included in income tax expense and in 2016, the benefit was recorded as additional paid-in-capital in the Consolidated Balance Sheets due to the adoption of accounting guidance on January 1, 2017. This guidance requires all income tax effects of share-based awards to be recognized as income tax expense or benefit in the income statement when the awards vest or are settled on a prospective basis, as opposed to stockholders’ equity.

We are subject to examination by federal, state and local, and foreign tax authorities. We regularly assess the likelihood of additional assessments by each jurisdiction and have established tax reserves that we believe are adequate in relation to the potential for additional assessments. We believe that the resolution of tax matters will not have a material effect on our financial condition but may be material to our operating results for a particular period and the effective tax rate for that period.

The effective tax rate may vary from period to period depending on, among other factors, the geographic and business mix of earnings and losses. These same and other factors, including the history of pre-tax earnings and losses, are taken into account in assessing the ability to realize deferred tax assets.

Deferred Income Taxes

The temporary differences, which give rise to our deferred tax assets and (liabilities), consisted of the following:



	December 31,
	2018			2017
Deferred tax assets:	(in millions)
Deferred revenues	$	19		$	25
U.S. federal net operating loss	—			1
Foreign net operating loss	23			30
State net operating loss	4			4
Compensation and benefits	33			42
Foreign currency translation	—			292
Tax credits	—			7
Federal benefit of uncertain tax positions	17			—
Other	25			20
Gross deferred tax assets	121			421
Less: valuation allowance	(23		)	(30		)
Total deferred tax assets, net of valuation allowance	$	98		$	391

Deferred tax liabilities:
Amortization of software development costs and depreciation	$	(41	)	$	(47	)
Amortization of acquired intangible assets	(498		)	(510		)
Investments	(34		)	(26		)
Other	(22		)	(19		)
Gross deferred tax liabilities	(595		)	(602		)
Net deferred tax liabilities	$	(497	)	$	(211	)
Reported as:
Non-current deferred tax assets⁽¹⁾	4			14
Deferred tax liabilities, net	(501		)	(225		)
Net deferred tax liabilities	$	(497	)	$	(211	)

____________


⁽¹⁾	Included in other non-current assets in the Consolidated Balance Sheets.

A valuation allowance has been established with regards to the tax benefits associated with certain net operating losses, or NOLs, as it is more likely than not that these benefits will not be realized in the foreseeable future.

As of December 31, 2018, the expiration dates for the NOLs are as follows:



Jurisdiction	Amount		Expiration Date
	(in millions)
Foreign NOL	$	3	2019-2025
Foreign NOL	20		No expiration date
State NOL	4		2025-2036

Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:



	Year Ended December 31,
	2018			2017			2016
	(in millions)
Beginning balance	$	45		$	48		$	40
Additions as a result of tax positions taken in prior periods	28			2			9
Additions as a result of tax positions taken in the current period	6			5			3
Reductions related to settlements with taxing authorities	(23		)	—			(4		)
Reductions as a result of lapses of the applicable statute of limitations	(4		)	(10		)	—
Ending balance	$	52		$	45		$	48

As of December 31, 2018, we had $43 million of unrecognized tax benefits, $45 million as of December 31, 2017 and $48 million as of December 31, 2016 which, if recognized in the future, would affect our effective tax rate. Nasdaq believes it is reasonably possible that our unrecognized tax benefits could decrease within the next 12 months by as much as $12 million, principally as a result of potential resolutions or settlements of prior years’ tax items.

We recognize interest and/or penalties related to income tax matters in the provision for income taxes in our Consolidated Statements of Income and were $2 million for the year ended December 31, 2018, $1 million for 2017 and $2 million for 2016. Accrued interest and penalties, net of tax effect were $10 million as of December 31, 2018 and $9 million as of December 31, 2017.

Tax Audits

Nasdaq and its eligible subsidiaries file a consolidated U.S. federal income tax return and applicable state and local income tax returns and non-U.S. income tax returns. Federal income tax returns for the years 2008 through 2014 are currently under examination by the Internal Revenue Services and we are subject to examination by the Internal Revenue Service for years 2015 through 2017. Several state tax returns are currently under examination by the respective tax authorities for the years 2007 through 2016 and we are subject to examination for the year 2017. Non-U.S. tax returns are subject to examination by the respective tax authorities for the years 2009 through 2017. Although the results of such examinations may have an impact on our unrecognized tax benefits, we do not anticipate that such impact will be material to our consolidated financial position or results of operations. In addition, we do not anticipate that the amount of unrecognized tax benefits as of December 31, 2018 will decrease in the next twelve months as we do not expect to settle any material tax audits.

The Swedish Tax Agency has disallowed certain interest expense deductions for the years 2013 - 2016. We appealed to the Lower Administrative Court for the years 2013 - 2015. In the first quarter of 2018, the Lower Administrative Court denied our appeal. We have appealed to the Administrative Court of Appeal. Through March 31, 2018, we had recorded tax benefits of $56 million associated with this matter. We continue to pay all assessments from the Swedish Tax Agency while this matter is pending and have paid $40 million through December 31, 2018. In the second quarter of 2018, the Administrative Court of Appeal decided similar cases against other taxpayers. Although we continue to assert the validity of these interest expense deductions, the decisions of the court lead us to conclude that we can no longer assert that we are more than likely to be successful in our appeal. As such, in 2018, we recorded tax expense of $41 million, or $0.24 per diluted share, which is net of any related U.S. tax benefits and reflects the impact of foreign currency translation. We expect to record future quarterly net tax expense of $1 million related to this matter.

Tax Cuts and Jobs Act

The Tax Cuts and Jobs Act contained several key provisions, including a reduction of the U.S. corporate income tax rate from 35% to 21%. It also imposed a transition tax on unremitted aggregate accumulated earnings of non-U.S. subsidiaries, which did not impact us and the act also created a new requirement to provide U.S. tax on foreign earnings, global intangible low-taxed income, or GILTI, which was immaterial for 2018. To the extent that we incur future expense under the GILTI provisions, we will record the expense as a component of income tax expense as a current-period expense when incurred. We were required to remeasure all of our U.S. deferred tax assets and liabilities as of December 22, 2017 and record the impact of such remeasurement in our 2017 financial statements. The net effect of applying the provisions of the act on our 2017 Consolidated Statement of Income was a non-cash provisional tax benefit of $89 million, substantially all of which reflects the estimated impact associated with the remeasurement of our net U.S. deferred tax liability at the lower U.S. federal corporate income tax rate.

SAB 118 provided guidance which allowed us to record provisional amounts during a measurement period of up to one year from the enactment date to finalize the recording of any related tax impacts. During the fourth quarter of 2018, we completed our accounting for the tax effects of the act, finalizing our analysis of the act and subsequent guidance issued by the U.S. Internal Revenue Service. As a result, we recorded a $290 million non-cash tax charge, reducing deferred tax assets relating to foreign currency translation.

Topic 220

On January 1, 2018, we adopted Topic 220. See “Income Statement - Reporting Comprehensive Income,” of “Recent Accounting Pronouncements,” of Note 2, “Summary of Significant Accounting Policies,” for further discussion of this standard. As a result of the adoption of this standard, we recorded a reclassification of $417 million related to the Tax Cuts and Jobs Act from accumulated other comprehensive loss to retained earnings within stockholders’ equity in the Consolidated Balance Sheets.

Restructuring Charges

12 Months Ended

Dec. 31, 2018

Restructuring and Related Activities [Abstract]

Restructuring Charges

2015 Restructuring Plan

During the first quarter of 2015, we performed a comprehensive review of our processes, businesses and systems in a company-wide effort to improve performance, cut costs, and reduce spending. This restructuring plan was completed in the second quarter of 2016.

The following table presents a summary of restructuring plan charges in the Consolidated Statements of Income:



	Year Ended
	December 31, 2016
	(in millions)
Severance and other termination benefits	$	22
Facilities-related	1
Asset impairments	8
Other	10
Total restructuring charges	$	41

For the year ended December 31, 2016, we recognized restructuring charges totaling $41 million, including severance costs of $22 million related to workforce reductions of 201 positions across our organization, $8 million for asset impairments, primarily related to fixed assets and capitalized software that were retired and $10 million of other charges.

Restructuring Reserve

Severance

As of December 31, 2016, an accrued severance balance of $17 million was included in other current liabilities in the Consolidated Balance Sheets and was paid during 2017.

Commitments, Contingencies and Guarantees	12 Months Ended
Commitments, Contingencies and Guarantees	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees Guarantees Issued and Credit Facilities Available In addition to the default fund contributions and margin collateral pledged by clearing members discussed in Note 15, “Clearing Operations,” we have obtained financial guarantees and credit facilities which are guaranteed by us through counter indemnities, to provide further liquidity related to our clearing businesses. Financial guarantees issued to us totaled $12 million as of December 31, 2018 and $14 million as of December 31, 2017. As discussed in “Other Credit Facilities,” of Note 9, “Debt Obligations,” clearing-related credit facilities, which are available in multiple currencies, totaled $220 million as of December 31, 2018 and $187 million as of December 31, 2017, in available liquidity, none of which was utilized. Execution Access is an introducing broker which operates the trading platform for our Fixed Income business to trade in U.S. Treasury securities. Execution Access has a clearing arrangement with Industrial and Commercial Bank of China Financial Services LLC, or ICBC. As of December 31, 2018, we have contributed $15 million of clearing deposits to ICBC in connection with this clearing arrangement. These deposits are recorded in other current assets in our Consolidated Balance Sheets. Some of the trading activity in Execution Access is cleared by ICBC through the Fixed Income Clearing Corporation, with ICBC acting as agent. Execution Access assumes the counterparty risk of clients that do not clear through the Fixed Income Clearing Corporation. Counterparty risk of clients exists for Execution Access between the trade date and the settlement date of the individual transactions, which is at least one business day (or more, if specified by the U.S. Treasury issuance calendar). Counterparties that do not clear through the Fixed Income Clearing Corporation are subject to a credit due diligence process and may be required to post collateral, provide principal letters, or provide other forms of credit enhancement to Execution Access for the purpose of mitigating counterparty risk. Daily position trading limits are also enforced for such counterparties. We believe that the potential for us to be required to make payments under these arrangements is mitigated through the pledged collateral and our risk management policies. Accordingly, no contingent liability is recorded in the Consolidated Balance Sheets for these arrangements. However, no guarantee can be provided that these arrangements will at all times be sufficient. Lease Commitments We lease some of our office space under non-cancelable operating leases with third parties and sublease office space to third parties. Some of our lease agreements contain renewal options and escalation clauses based on increases in property taxes and building operating costs. Other Guarantees Through our clearing operations in the financial markets, Nasdaq Clearing is the legal counterparty for, and guarantees the performance of, its clearing members. See Note 15, “Clearing Operations,” for further discussion of Nasdaq Clearing performance guarantees. We have provided a guarantee related to lease obligations for The Nasdaq Entrepreneurial Center, Inc., which is a not-for-profit organization designed to convene, connect and engage aspiring and current entrepreneurs. This entity is not included in the consolidated financial statements of Nasdaq. We believe that the potential for us to be required to make payments under these arrangements is unlikely. Accordingly, no contingent liability is recorded in the Consolidated Balance Sheets for the above guarantees. Non-Cash Contingent Consideration As part of the purchase price consideration of a prior acquisition, we have agreed to future annual issuances of 992,247 shares of Nasdaq common stock which approximated certain tax benefits associated with the transaction. Such contingent future issuances of Nasdaq common stock will be paid ratably through 2027 if Nasdaq’s total gross revenues equal or exceed $25 million in each such year. The contingent future issuances of Nasdaq common stock are subject to anti-dilution protections and acceleration upon certain events. Escrow Agreements In connection with prior acquisitions, we entered into escrow agreements to secure the payment of post-closing adjustments and to ensure other closing conditions. As of December 31, 2018, these escrow agreements provide for future payment of $12 million which is included in other current liabilities in the Consolidated Balance Sheets. Routing Brokerage Activities One of our broker-dealer subsidiaries, Nasdaq Execution Services, provides a guarantee to securities clearinghouses and exchanges under its standard membership agreements, which require members to guarantee the performance of other members. If a member becomes unable to satisfy its obligations to a clearinghouse or exchange, other members would be required to meet its shortfalls. To mitigate these performance risks, the exchanges and clearinghouses often require members to post collateral, as well as meet certain minimum financial standards. Nasdaq Execution Services’ maximum potential liability under these arrangements cannot be quantified. However, we believe that the potential for Nasdaq Execution Services to be required to make payments under these arrangements is unlikely. Accordingly, no contingent liability is recorded in the Consolidated Balance Sheets for these arrangements. Acquisition of Cinnober For further discussion of our acquisition of Cinnober, see “Acquisition of Cinnober,” of Note 3, “Acquisitions and Divestiture,” to the consolidated financial statements. Other Commitment We have a 40.0% ownership in OCC. Under the OCC's capital plan, the OCC shareholders have committed to contribute up to $200 million in equity capital if certain capital thresholds are breached, including up to $80 million to be contributed by Nasdaq. See “Equity Method Investments,” of Note 6, “Investments,” for further discussion of our equity method investment in OCC. Offer for Oslo Børs VPS For further discussion of our offer for Oslo Børs VPS, see “Offer for Oslo Børs VPS,” of Note 21, “Subsequent Events.” Legal and Regulatory Matters Litigation As previously disclosed, we are named as one of many defendants in City of Providence v. BATS Global Markets, Inc., et al., 14 Civ. 2811 (S.D.N.Y.), which was filed on April 18, 2014 in the United States District Court for the Southern District of New York. The district court appointed lead counsel, who filed an amended complaint on September 2, 2014. The amended complaint names as defendants seven national exchanges, as well as Barclays PLC, which operated a private alternative trading system. On behalf of a putative class of securities traders, the plaintiffs allege that the defendants engaged in a scheme to manipulate the markets through high-frequency trading; the amended complaint asserts claims against us under Section 10(b) of the Exchange Act and Rule 10b-5, as well as under Section 6(b) of the Exchange Act. The plaintiffs seek injunctive and monetary relief of an unspecified amount. We filed a motion to dismiss the amended complaint on November 3, 2014. In response, the plaintiffs filed a second amended complaint on November 24, 2014, which names the same defendants and alleges essentially the same violations. We then filed a motion to dismiss the second amended complaint on January 23, 2015. On August 26, 2015, the district court entered an order dismissing the second amended complaint in its entirety with prejudice, concluding that most of the plaintiffs’ theories were foreclosed by absolute immunity and in any event that the plaintiffs failed to state any claim. The plaintiffs appealed the judgment of dismissal to the United States Court of Appeals for the Second Circuit. On December 19, 2017, the Second Circuit issued an opinion vacating the district court’s judgment of dismissal and remanding to the district court for further proceedings. The exchanges filed a petition before the Second Circuit seeking panel or en banc rehearing on January 31, 2018, which the Second Circuit denied on March 13, 2018. On May 18, 2018, the exchanges filed a motion to dismiss the amended complaint, raising issues not addressed in the proceedings to date. Given the preliminary nature of the proceedings, we are unable to estimate what, if any, liability may result from this litigation. However, we believe that the claims are without merit and will continue to litigate vigorously. Nasdaq Commodities Clearing Default During September 2018, a clearing member of Nasdaq Clearing's commodities market was declared in default. Consistent with our regulatory obligations, we notified all relevant regulators and are cooperating fully with information requests. We are engaging in discussions with the other members regarding the default and recovery process towards the defaulting member. We are unable to predict the outcome or exact timing of this matter. See “Nasdaq Commodities Clearing Default,” of Note 15, “Clearing Operations,” for further information on this event. SEC Decisions In recent years, certain industry groups have challenged the level of fees that U.S. exchanges charge for market data and connectivity. We have defeated two challenges in federal appeals court pertaining to market data and an additional challenge at the administrative level within the SEC. However, in October 2018, the SEC reversed that administrative decision and found that Nasdaq had not met a burden of demonstrating that certain challenged fees were fair and reasonable; we estimate that this decision will reduce our revenues by approximately $1 million. Nasdaq has appealed this decision to the U.S. Court of Appeals for the District of Columbia Circuit. In addition, the SEC remanded a series of additional challenges to market data and connectivity fees back to Nasdaq for further consideration. Nasdaq has also appealed this decision to the U.S. Court of Appeals for the District of Columbia Circuit. We are unable to predict the outcome or the timing of the ultimate resolution of these matters. Other Matters Except as disclosed above and in prior reports filed under the Exchange Act, we are not currently a party to any litigation or proceeding that we believe could have a material adverse effect on our business, consolidated financial condition, or operating results. However, from time to time, we have been threatened with, or named as a defendant in, lawsuits or involved in regulatory proceedings. In the normal course of business, Nasdaq discusses matters with its regulators raised during regulatory examinations or otherwise subject to their inquiries. Management believes that censures, fines, penalties or other sanctions that could result from any ongoing examinations or inquiries will not have a material impact on its consolidated financial position or results of operations. However, we are unable to predict the outcome or the timing of the ultimate resolution of these matters, or the potential fines, penalties or injunctive or other equitable relief, if any, that may result from these matters. Tax Audits We are engaged in ongoing discussions and audits with taxing authorities on various tax matters, the resolutions of which are uncertain. Currently, there are matters that may lead to assessments, some of which may not be resolved for several years. Based on currently available information, we believe we have adequately provided for any assessments that could result from those proceedings where it is more likely than not that we will be assessed. We review our positions on these matters as they progress. See “Tax Audits,” of Note 17, “Income Taxes,” for further discussion.

Business Segments

12 Months Ended

Dec. 31, 2018

Segment Reporting [Abstract]

Business Segments

We manage, operate and provide our products and services in four business segments: Market Services, Corporate Services, Information Services and Market Technology. See Note 1, “Organization and Nature of Operations,” for further discussion of our reportable segments. In early 2018, we realigned our businesses to better serve the needs of our corporate clients. As a result, beginning in the second quarter of 2018, our BWise internal audit, regulatory compliance management, and operational risk management software solutions are now offered as part of governance, risk & compliance products and services within our Corporate Solutions business. BWise was previously part of our Market Technology segment. We have restated prior periods to conform to the current year presentation.

Our management allocates resources, assesses performance and manages these businesses as four separate segments. We evaluate the performance of our segments based on several factors, of which the primary financial measure is operating income. Results of individual businesses are presented based on our management accounting practices and structure.

The following table presents certain information regarding our operating segments for the years ended December 31, 2018, 2017 and 2016:



	Market Services			Corporate Services		Information Services		Market Technology		Corporate Items			Consolidated
	(in millions)
Year Ended December 31, 2018
Total revenues	$	2,709		$	528	$	714	$	270	$	56		$	4,277
Transaction-based expenses	(1,751		)	—		—		—		—			(1,751		)
Revenues less transaction-based expenses	958			528		714		270		56			2,526
Depreciation and amortization	95			41		51		$	21	2			210
Operating income (loss)	544			163		460		34		(173		)	1,028
Total assets	10,299			734		3,352		467		848			15,700
Purchase of property and equipment	28			29		17		37		—			111
Year Ended December 31, 2017
Total revenues	$	2,418		$	501	$	588	$	247	$	194		$	3,948
Transaction-based expenses	(1,537		)	—		—		—		—			(1,537		)
Revenues less transaction-based expenses	881			501		588		247		194			2,411
Depreciation and amortization	95			44		26		14		9			188
Operating income (loss)	481			158		418		57		(123		)	991
Total assets	9,471			865		3,420		572		1,026			15,354
Purchase of property and equipment	59			41		10		34		—			144
Year Ended December 31, 2016
Total revenues	$	2,255		$	477	$	540	$	241	$	191		$	3,704
Transaction-based expenses	(1,428		)	—		—		—		—			(1,428		)
Revenues less transaction-based expenses	827			477		540		241		191			2,276
Depreciation and amortization	87			42		18		13		10			170
Operating income (loss)	450			130		383		73		(200		)	836
Total assets	8,626			1,263		2,439		497		586			13,411
Purchase of property and equipment	62			37		8		27		—			134

Certain amounts are allocated to corporate items in our management reports as we believe they do not contribute to a meaningful evaluation of a particular segment's ongoing operating performance. These items include the following:

2018 Divestiture: We have included in corporate items the revenues and expenses of the Public Relations Solutions and Digital Media Services businesses which were part of the Corporate Solutions business within our Corporate Services segment as these businesses were sold in April 2018. See “2018 Divestiture,” of Note 3, “Acquisitions and Divestiture,” for further discussion.

Amortization expense of acquired intangible assets: We amortize intangible assets acquired in connection with various acquisitions. Intangible asset amortization expense can vary from period to period due to episodic acquisitions completed, rather than from our ongoing business operations. As such, if intangible asset amortization is included in performance measures, it is more difficult to assess the day-to-day operating performance of the segments, and the relative operating performance of the segments between periods. Management does not consider intangible asset amortization expense for the purpose of evaluating the performance of our segments or their managers or when making decisions to allocate resources. Therefore, we believe performance measures excluding intangible asset amortization expense provide management with a more useful representation of our segments' ongoing activity in each period.

Merger and strategic initiatives expense: We have pursued various strategic initiatives and completed a divestiture and a number of acquisitions in recent years which have resulted in expenses which would not have otherwise been incurred. These expenses generally include integration costs, as well as legal, due diligence and other third party transaction costs. The frequency and the amount of such expenses vary significantly based on the size, timing and complexity of the transaction.

Clearing Default: For the year ended December 31, 2018, we recorded $31 million in expense related to the clearing default. In September 2018, we recorded an $8 million loss relating to this default. In December 2018, we recorded a $23 million charge as a result of initiating a capital relief program. See “Nasdaq Commodities Clearing Default,” of Note 15, “Clearing Operations,” for further discussion of the default. We have excluded these charges as we believe they are non-recurring, as there has never been a loss due to member default in our clearinghouse, and they should be excluded when evaluating the ongoing operating performance of the Market Services segment. Any expenses associated with the enhancement of processes and procedures relating to our clearing business will be reflected within the Market Services segment.

Other significant items: We have included certain other charges or gains in corporate items, to the extent we believe they should be excluded when evaluating the ongoing operating performance of each individual segment. For 2018, other significant items primarily included charges related to uncertain positions pertaining to sales and use tax and VAT and certain litigation costs. For 2017, other significant items primarily included loss on extinguishment of debt. For 2016, other significant items primarily included restructuring charges of $41 million which were associated with our 2015 restructuring plan, a regulatory fine received by our Nordic exchanges and clearinghouse, accelerated expense for equity awards previously granted due to the retirement of the company’s former CEO, and the release of a sublease loss reserve due to the early exit of a facility. We believe the exclusion of such amounts allows management and investors to better understand the ongoing financial results of each segment.

Accordingly, we do not allocate these costs for purposes of disclosing segment results because they do not contribute to a meaningful evaluation of a particular segment’s ongoing operating performance.

* * * * * *

A summary of our corporate items is as follows:



	Year Ended December 31,
	2018			2017			2016
	(in millions)
Revenues - divested businesses	$	56		$	194		$	191
Expenses:
Amortization expense of acquired intangible assets	109			92			82
Merger and strategic initiatives expense	21			44			76
Clearing default	31			—			—
Extinguishment of debt	—			10			—
Restructuring charges	—			—			41
Regulatory matter	—			—			6
Expenses - divested businesses	51			167			168
Executive compensation	—			—			12
Other	17			4			6
Total expenses	229			317			391
Operating loss	$	(173	)	$	(123	)	$	(200	)

Total assets increased $346 million as of December 31, 2018 compared with December 31, 2017 primarily due to an increase in default funds and margin deposits (with a corresponding increase in current liabilities), due to higher cash default fund contributions directly related to member exposure and an increase in margin level requirements as a result of the Nasdaq Commodities clearing default in September 2018. This increase was partially offset by a decrease in goodwill and intangible assets, net reflecting the impact of changes in foreign exchange rates and amortization of intangible assets. Total assets increased $2.0 billion as of December 31, 2017 compared with December 31, 2016 primarily due to an increase in default funds and margin deposits (with a corresponding increase in current liabilities), reflecting an increase in cash margin deposits pledged by members of our Nasdaq Clearing business due to an increase in clearing volume. Also contributing to the increase was an increase in goodwill and intangible assets associated with our 2017 and 2016 acquisitions.

For further discussion of our segments’ results, see “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations-Segment Operating Results.”

Geographic Data

The following table presents total revenues and property and equipment, net by geographic area for 2018, 2017 and 2016. Revenues are classified based upon the location of the customer. Property and equipment information is based on the physical location of the assets. On January 1, 2018, we adopted Topic 606 using the full retrospective method which required restatement of 2017 and 2016 financial statements.



	Total Revenues		Property and Equipment, Net
2018:	(in millions)
United States	$	3,379	$	224
All other countries	898		152
Total	$	4,277	$	376
2017:
United States	$	3,081	$	247
All other countries	867		153
Total	$	3,948	$	400
2016:
United States	$	2,679	$	244
All other countries	1,025		118
Total	$	3,704	$	362

Our property and equipment, net for all other countries primarily includes assets held in Sweden.

No single customer accounted for 10.0% or more of our revenues in 2018, 2017 and 2016.

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Acquisition of Cinnober For further discussion of our acquisition of Cinnober, see “Acquisition of Cinnober,” of Note 3, “Acquisitions and Divestiture,” to the consolidated financial statements. Offer for Oslo Børs VPS In February 2019, we, through our indirect wholly-owned subsidiary Nasdaq AB, made a public offer, or the Offer, to acquire all of the issued shares of Oslo Børs VPS Holding ASA, or Oslo Børs VPS, at NOK 152 per share plus interest payments at a rate of 6% per annum on the Offer price, pro-rated per day from January 29, 2019 until the conditions to the Offer have been fulfilled or waived. The Offer price values the entire issued share capital of Oslo Børs VPS at NOK 6,537 million, or approximately $770 million. Oslo Børs VPS’ board of directors has unanimously recommended that its shareholders accept the Offer. The acceptance period will be open from February 4, 2019 to March 4, 2019 and is subject to extension or re-opening. The Offer is subject to the fulfillment or waiver of certain customary conditions, including but not limited to acceptances from shareholders holding 90% or more of the shares of Oslo Børs VPS, certain regulatory clearances, limited confirmatory due diligence and completion of the Offer by December 31, 2019. Agreement to Sell BWise In February 2019, we entered into an agreement with SAI Global to sell BWise, our internal audit, regulatory compliance management, and operational risk management software that comprises our governance, risk and compliance product offering. Subject to regulatory approvals, works council and other representative body consultations and notifications in applicable jurisdictions, as well as other customary closing conditions, the transaction is expected to close in the first half of 2019. BWise is part of our Corporate Solutions business within our Corporate Services segment.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Basis of Presentation

Basis of Presentation and Principles of Consolidation

Consolidation

Use of Estimates

Foreign Currency

Cash and Cash Equivalents

Restricted Cash

Receivables, net

Investments

Purchases and sales of investment securities are recognized on settlement date.

Financial investments, at fair value

Equity Securities

Equity Method Investments

Default Funds and Margin Deposits

Derivative Financial Instruments and Hedging Activities

Non-Designated Derivatives

As of December 31, 2018 and 2017, the fair value amounts of our derivative instruments were immaterial.

Net Investment Hedges

Property and Equipment, net

Leasehold improvements are amortized using the straight-line method over the shorter of their estimated useful lives or the remaining term of the related lease.

Goodwill and Indefinite-Lived Intangible Assets

The quantitative goodwill test consists of two steps:


•	The first step compares the fair value of each reporting unit with its carrying amount, including goodwill. If the reporting unit’s fair value exceeds its carrying amount, goodwill is not impaired.


•	If the fair value of a reporting unit is less than its carrying amount, the second step of the goodwill test is performed to measure the amount of impairment, if any. An impairment is equal to the excess of the carrying amount of goodwill over its fair value.

Valuation of Other Long-Lived Assets

Revenue From Contracts With Customers



Adjustments to Reflect Adoption of Topic 606
	Year Ended December 31,
	2017			2016
	(in millions)
Revenues less transaction-based expenses:
Market Services	$	—		$	—
Corporate Services	(3		)	(3		)
Information Services	—			—
Market Technology	(14		)	2
Total revenues less transaction-based expenses	$	(17	)	$	(1	)

Total operating expenses⁽¹⁾	$	(9	)	$	2

Income before income taxes	$	(8	)	$	(3	)
Income tax provision	(3		)	(1		)
Net income attributable to Nasdaq	$	(5	)	$	(2	)
Diluted earnings per share	$	(0.03	)	$	(0.01	)

____________

⁽¹⁾ Adjustment to reflect the adoption of Topic 606 for the year ended December 31, 2017 and 2016 primarily pertain to our Market Technology business.



Adjustments to Reflect Adoption of Topic 606
	December 31, 2017			December 31, 2016
	(in millions)
Assets:
Other current assets	$	(19	)	$	(15	)
Other non-current assets	(38		)	(46		)
Deferred tax assets	2			(1		)
Total assets	$	(55	)	$	(62	)

Liabilities:
Deferred revenue	$	(28	)	$	(24	)
Non-current deferred revenue	(20		)	(36		)
Total liabilities	(48		)	(60		)

Nasdaq stockholders' equity:
Retained earnings	$	(7	)	$	(2	)
Total Nasdaq stockholders' equity	(7		)	(2		)

Total liabilities and equity	$	(55	)	$	(62	)

Additional disclosures required by Topic 606 are provided below.

Contract Balances

Revenue Recognition

Market Services

Transaction-Based Trading and Clearing

Trade Management Services

Corporate Services

Corporate Solutions

Listing Services

Information Services

Market Data Products

Market data products revenues are earned from U.S. and European proprietary market data products. In the U.S., we also earn revenues from U.S. shared tape plans.

Market Data Products Revenue Sharing


•	We are the administrator for the plan, in addition to being a participant in the plan. In our unique role as administrator, we facilitate the collection and dissemination of revenues on behalf of the plan participants. As a participant, we share in the net distribution of revenues according to the plan on the same terms as all other plan participants.


•	The operating committee of the plan, which is comprised of representatives from each of the participants, including us solely in our capacity as a plan participant, is responsible for setting the level of fees to be paid by distributors and subscribers and taking action in accordance with the provisions of the plan, subject to SEC approval.


•	Risk of loss on the revenue is shared equally among plan participants according to the plan.

The exchanges that comprise Nasdaq Nordic and Nasdaq Baltic do not have any market data products revenue sharing agreements.

Index

Investment Data & Analytics

Investment data & analytics revenues are earned from investment content and analytics products. We earn revenues primarily based on the number of content and analytics subscribers and distributors.

Market Technology

Other Revenues

Earnings Per Share

Pension and Post-Retirement Benefits

Share-Based Compensation

Merger and Strategic Initiatives

Leases

In February 2016, the FASB issued ASU 2016-02, “Leases.” We adopted this new guidance on January 1, 2019.

Fair Value Measurements


•	Level 1-Quoted prices for identical instruments in active markets.


•	Level 2-Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable.


•	Level 3-Instruments whose significant value drivers are unobservable.

This hierarchy requires the use of observable market data when available.

Tax Matters

Assets Held for Sale

We classify assets or disposal groups as held for sale in the period in which all of the following criteria are met:


•	management commits to a plan to sell;


•	the asset or disposal group is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such assets or disposal groups;


•	an active program to locate a buyer and other actions required to complete the plan to sell have been initiated;


•	the sale is probable within one year;


•	the asset or disposal group is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and


•	it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn.

Recent Accounting Pronouncements



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Intangibles - Goodwill and Other - Internal-Use Software In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract.”	This ASU clarifies the accounting for implementation costs of a hosting arrangement and aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). Capitalized implementation costs should be expensed over the term of the hosting arrangement and recognized in the same line item in the statement of income as the hosted service costs. Payments for capitalized implementation costs should be classified in the statement of cash flows in the same manner as payments made for fees associated with the hosting element. Capitalized implementation costs should be presented in the balance sheet in the same line item as a prepayment for the fees of the associated hosting arrangement.	January 1, 2020, with early adoption permitted. We early adopted this standard as of July 1, 2018.	There was no impact to the financial statements as a result of the adoption of this standard, as we are currently accounting for costs incurred in a cloud computing arrangement in accordance with the standard.
Fair Value Measurements In August 2018, the FASB issued ASU 2018-13 “Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement.”	This ASU modifies the disclosure requirements on fair value measurements by removing certain disclosure requirements related to the fair value hierarchy, modifying existing disclosure requirements related to measurement uncertainty, and adding new requirements, mainly for Level 3 fair value measurements.	January 1, 2020, with early adoption permitted. We early adopted this standard as of July 1, 2018 on a prospective basis.	There was no impact to the financial statements or our disclosures as a result of the adoption of this standard.



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Income Statement - Reporting Comprehensive Income In February 2018, the FASB issued ASU 2018-02, “Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (Topic 220).”	This ASU was issued to address the income tax accounting treatment of the stranded tax effects within other comprehensive income due to the prohibition of backward tracing due to an income tax rate change that was initially recorded in other comprehensive income. This issue came about from the enactment of the Tax Cuts and Jobs Act that changed our income tax rate from 35% to 21%. The ASU changed current accounting whereby an entity may elect to reclassify the stranded tax effect from accumulated other comprehensive income to retained earnings.	January 1, 2019, with early adoption permitted. We early adopted this standard as of January 1, 2018.	As a result of the adoption of this standard, we recorded a reclassification of $417 million related to the Tax Cuts and Jobs Act from accumulated other comprehensive loss to retained earnings within stockholders’ equity in the Consolidated Balance Sheets. See “Tax Cuts and Jobs Act,” of Note 17, “Income Taxes,” for further discussion.
Goodwill In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment.”	This ASU simplifies how an entity is required to test goodwill for impairment and removes the second step of the goodwill impairment test, which required a hypothetical purchase price allocation if the fair value of a reporting unit is less than its carrying amount. Goodwill impairment will now be measured using the difference between the carrying amount and the fair value of the reporting unit and the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The amendments in this ASU should be applied on a prospective basis.	January 1, 2020, with early adoption permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017.	We do not anticipate a material impact on our consolidated financial statements at the time of adoption of this new standard as the carrying amounts of our reporting units have been less than their corresponding fair values in recent years. However, changes in future projections, market conditions and other factors may cause a change in the excess of fair value of our reporting units over their corresponding carrying amounts. We do not anticipate early adoption of this standard.



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Financial Instruments - Credit Losses In June 2016, the FASB issued ASU 2016-13, “Measurement of Credit Losses on Financial Instruments.”	This ASU changes the impairment model for certain financial instruments. The new model is a forward looking expected loss model and will apply to financial assets subject to credit losses and measured at amortized cost and certain off-balance sheet credit exposures. This includes loans, held-to-maturity debt securities, loan commitments, financial guarantees and net investments in leases, as well as trade receivables. For available-for-sale debt securities with unrealized losses, credit losses will be measured in a manner similar to today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of the securities.	January 1, 2020, with early adoption permitted as of January 1, 2019.	We will adopt this standard on January 1, 2020. We are currently assessing the impact that this standard will have on our consolidated financial statements.
Leases In February 2016, the FASB issued ASU 2016-02, “Leases.”	Under this ASU, at the commencement date, lessees will be required to recognize a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. This guidance is not applicable for leases with a term of 12 months or less. Recognition, measurement and presentation of expenses will depend on classification as a finance or operating lease. The guidance also requires certain quantitative and qualitative disclosures about leasing arrangements. Lessor accounting is largely unchanged. In transition, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach.	January 1, 2019.	See discussion below.

* * * * * *

Leases

Practical Expedients and Accounting Policy Elections

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Remaining Performance Obligation, Expected Timing of Satisfaction

For our market technology contracts, the following table summarizes the amount of the transaction price allocated to performance obligations that are unsatisfied as of December 31, 2018:



	(in millions)
2019	$	255
2020	183
2021	94
2022	58
2023	30
2024 and thereafter	75
Total	$	695

Disaggregation of Revenue

The following tables summarize the disaggregation of revenue by major product and service and by segment for the years ended December 31, 2018, 2017 and 2016:



	Year Ended December 31, 2018
	Market Services		Corporate Services		Information Services		Market Technology		Other Revenues		Consolidated
	(in millions)
Transaction-based trading and clearing, net	$	666	$	—	$	—	$	—	$	—	$	666
Trade management services	292		—		—		—		—		292
Corporate solutions	—		238		—		—		—		238
Listing services	—		290		—		—		—		290
Market data products	—		—		390		—		—		390
Index	—		—		206		—		—		206
Investment data & analytics	—		—		118		—		—		118
Market technology	—		—		—		270		—		270
Other revenues	—		—		—		—		56		56
Revenues less transaction-based expenses	$	958	$	528	$	714	$	270	$	56	$	2,526



	Year Ended December 31, 2017
	Market Services		Corporate Services		Information Services		Market Technology		Other Revenues		Consolidated
	(in millions)
Transaction-based trading and clearing, net	$	590	$	—	$	—	$	—	$	—	$	590
Trade management services	291		—		—		—		—		291
Corporate solutions	—		234		—		—		—		234
Listing services	—		267		—		—		—		267
Market data products	—		—		369		—		—		369
Index	—		—		171		—		—		171
Investment data & analytics	—		—		48		—		—		48
Market technology	—		—		—		247		—		247
Other revenues	—		—		—		—		194		194
Revenues less transaction-based expenses	$	881	$	501	$	588	$	247	$	194	$	2,411



	Year Ended December 31, 2016
	Market Services		Corporate Services		Information Services		Market Technology		Other Revenues		Consolidated
	(in millions)
Transaction-based trading and clearing, net	$	561	$	—	$	—	$	—	$	—	$	561
Trade management services	266		—		—		—		—		266
Corporate solutions	—		208		—		—		—		208
Listing services	—		269		—		—		—		269
Market data products	—		—		354		—		—		354
Index	—		—		149		—		—		149
Investment data & analytics	—		—		37		—		—		37
Market technology	—		—		—		241		—		241
Other revenues	—		—		—		—		191		191
Revenues less transaction-based expenses	$	827	$	477	$	540	$	241	$	191	$	2,276

Schedule of the Recent Accounting Pronouncements



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Intangibles - Goodwill and Other - Internal-Use Software In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract.”	This ASU clarifies the accounting for implementation costs of a hosting arrangement and aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). Capitalized implementation costs should be expensed over the term of the hosting arrangement and recognized in the same line item in the statement of income as the hosted service costs. Payments for capitalized implementation costs should be classified in the statement of cash flows in the same manner as payments made for fees associated with the hosting element. Capitalized implementation costs should be presented in the balance sheet in the same line item as a prepayment for the fees of the associated hosting arrangement.	January 1, 2020, with early adoption permitted. We early adopted this standard as of July 1, 2018.	There was no impact to the financial statements as a result of the adoption of this standard, as we are currently accounting for costs incurred in a cloud computing arrangement in accordance with the standard.
Fair Value Measurements In August 2018, the FASB issued ASU 2018-13 “Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement.”	This ASU modifies the disclosure requirements on fair value measurements by removing certain disclosure requirements related to the fair value hierarchy, modifying existing disclosure requirements related to measurement uncertainty, and adding new requirements, mainly for Level 3 fair value measurements.	January 1, 2020, with early adoption permitted. We early adopted this standard as of July 1, 2018 on a prospective basis.	There was no impact to the financial statements or our disclosures as a result of the adoption of this standard.



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Income Statement - Reporting Comprehensive Income In February 2018, the FASB issued ASU 2018-02, “Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income (Topic 220).”	This ASU was issued to address the income tax accounting treatment of the stranded tax effects within other comprehensive income due to the prohibition of backward tracing due to an income tax rate change that was initially recorded in other comprehensive income. This issue came about from the enactment of the Tax Cuts and Jobs Act that changed our income tax rate from 35% to 21%. The ASU changed current accounting whereby an entity may elect to reclassify the stranded tax effect from accumulated other comprehensive income to retained earnings.	January 1, 2019, with early adoption permitted. We early adopted this standard as of January 1, 2018.	As a result of the adoption of this standard, we recorded a reclassification of $417 million related to the Tax Cuts and Jobs Act from accumulated other comprehensive loss to retained earnings within stockholders’ equity in the Consolidated Balance Sheets. See “Tax Cuts and Jobs Act,” of Note 17, “Income Taxes,” for further discussion.
Goodwill In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment.”	This ASU simplifies how an entity is required to test goodwill for impairment and removes the second step of the goodwill impairment test, which required a hypothetical purchase price allocation if the fair value of a reporting unit is less than its carrying amount. Goodwill impairment will now be measured using the difference between the carrying amount and the fair value of the reporting unit and the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The amendments in this ASU should be applied on a prospective basis.	January 1, 2020, with early adoption permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017.	We do not anticipate a material impact on our consolidated financial statements at the time of adoption of this new standard as the carrying amounts of our reporting units have been less than their corresponding fair values in recent years. However, changes in future projections, market conditions and other factors may cause a change in the excess of fair value of our reporting units over their corresponding carrying amounts. We do not anticipate early adoption of this standard.



Accounting Standard	Description	Effective Date	Effect on the Financial Statements or Other Significant Matters
Financial Instruments - Credit Losses In June 2016, the FASB issued ASU 2016-13, “Measurement of Credit Losses on Financial Instruments.”	This ASU changes the impairment model for certain financial instruments. The new model is a forward looking expected loss model and will apply to financial assets subject to credit losses and measured at amortized cost and certain off-balance sheet credit exposures. This includes loans, held-to-maturity debt securities, loan commitments, financial guarantees and net investments in leases, as well as trade receivables. For available-for-sale debt securities with unrealized losses, credit losses will be measured in a manner similar to today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of the securities.	January 1, 2020, with early adoption permitted as of January 1, 2019.	We will adopt this standard on January 1, 2020. We are currently assessing the impact that this standard will have on our consolidated financial statements.
Leases In February 2016, the FASB issued ASU 2016-02, “Leases.”	Under this ASU, at the commencement date, lessees will be required to recognize a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. This guidance is not applicable for leases with a term of 12 months or less. Recognition, measurement and presentation of expenses will depend on classification as a finance or operating lease. The guidance also requires certain quantitative and qualitative disclosures about leasing arrangements. Lessor accounting is largely unchanged. In transition, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach.	January 1, 2019.	See discussion below.



Adjustments to Reflect Adoption of Topic 606
	Year Ended December 31,
	2017			2016
	(in millions)
Revenues less transaction-based expenses:
Market Services	$	—		$	—
Corporate Services	(3		)	(3		)
Information Services	—			—
Market Technology	(14		)	2
Total revenues less transaction-based expenses	$	(17	)	$	(1	)

Total operating expenses⁽¹⁾	$	(9	)	$	2

Income before income taxes	$	(8	)	$	(3	)
Income tax provision	(3		)	(1		)
Net income attributable to Nasdaq	$	(5	)	$	(2	)
Diluted earnings per share	$	(0.03	)	$	(0.01	)

____________

⁽¹⁾ Adjustment to reflect the adoption of Topic 606 for the year ended December 31, 2017 and 2016 primarily pertain to our Market Technology business.



Adjustments to Reflect Adoption of Topic 606
	December 31, 2017			December 31, 2016
	(in millions)
Assets:
Other current assets	$	(19	)	$	(15	)
Other non-current assets	(38		)	(46		)
Deferred tax assets	2			(1		)
Total assets	$	(55	)	$	(62	)

Liabilities:
Deferred revenue	$	(28	)	$	(24	)
Non-current deferred revenue	(20		)	(36		)
Total liabilities	(48		)	(60		)

Nasdaq stockholders' equity:
Retained earnings	$	(7	)	$	(2	)
Total Nasdaq stockholders' equity	(7		)	(2		)

Total liabilities and equity	$	(55	)	$	(62	)

Acquisitions and Divestiture (Tables)

12 Months Ended

Dec. 31, 2018

Business Combinations [Abstract]

Schedule of Business Acquisitions, by Acquisition

2017 Acquisitions



	Purchase Consideration		Total Net Liabilities Acquired			Total Net Deferred Tax Liability			Acquired Intangible Assets		Goodwill
	(in millions)
eVestment	$	744	$	(10	)	$	(96	)	$	405	$	445

2016 Acquisitions



	Purchase Consideration		Total Net Assets (Liabilities) Acquired			Total Net Deferred Tax Liability			Acquired Intangible Assets		Goodwill
	(in millions)
ISE	$	1,070	$	83		$	(185	)	$	623	$	549
Boardvantage	242		28			(38		)	111		141
Marketwired	111		(1		)	(5		)	31		86
Nasdaq Canada	116		6			(20		)	76		54

Acquired Finite Lived Intangible Assets in Acquisition



	2017			2016
	eVestment			ISE			Boardvantage			Marketwired			Nasdaq Canada
	($ in millions)
Exchange registrations	$	—		$	467		$	—		$	—		$	—
Discount rate used	—			8.6		%	—			—			—
Estimated average useful life	—			Indefinite			—			—			—
Customer relationships	$	378		$	148		$	103		$	29		$	76
Discount rate used	9.3		%	9.1		%	15.5		%	16.4		%	10.3		%
Estimated average useful life	14 years			13 years			14 years			6 years			17 years
Trade name	$	13		$	8		$	2		$	2		$	—
Discount rate used	9.2		%	8.6		%	15.0		%	15.8		%	—
Estimated average useful life	8 years			Indefinite			1 year			2 years			—
Technology	$	14		$	—		$	6		$	—		$	—
Discount rate used	9.2		%	—			15.5		%	—			—
Estimated average useful life	8 years			—			5 years			—			—
Total intangible assets	$	405		$	623		$	111		$	31		$	76

Assets and Liabilities Held For Sale (Tables)

12 Months Ended

Dec. 31, 2018

Discontinued Operations and Disposal Groups [Abstract]

Schedule of carrying amounts of assets and liabilities classified as held for sale

The carrying amounts of the major classes of assets and liabilities that were classified as held for sale at December 31, 2018 and 2017 were as follows:



	December 31, 2018		December 31, 2017
	(in millions)
Receivables, net	$	13	$	27
Property and equipment, net	10		21
Goodwill⁽¹⁾	47		202
Intangible assets, net⁽²⁾	16		38
Other assets	3		9
Total assets held for sale⁽³⁾	$	89	$	297

Deferred tax liabilities	$	4	$	16
Deferred revenue	12		2
Other current liabilities	4		27
Total liabilities held for sale⁽⁴⁾	$	20	$	45

____________


⁽¹⁾	The assignment of goodwill was based on the relative fair value of the disposal group and the portion of the remaining reporting unit.

⁽²⁾Primarily represents customer relationships.

⁽³⁾Included in other current assets in the Consolidated Balance Sheets as of December 31, 2018 and 2017.

⁽⁴⁾Included in other current liabilities in the Consolidated Balance Sheets as of December 31, 2018 and 2017.

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 205
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721665-107760

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721671-107760

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 205
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-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721663-107760

+ Details

Goodwill and Acquired Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes in Goodwill

The following table presents the changes in goodwill by business segment during the year ended December 31, 2018:



	Market Services			Corporate Services			Information Services			Market Technology			Total
	(in millions)
Balance at December 31, 2017	$	3,546		$	490		$	2,362		$	188		$	6,586
Goodwill acquired	—			—			56			—			56
Measurement period adjustment	—			—			(8		)	—			(8		)
Reclassification of goodwill⁽¹⁾	—			29			—			(29		)	—
Goodwill reclassified to held for sale⁽²⁾	—			(47		)	—			—			(47		)
Foreign currency translation adjustment	(116		)	(17		)	(77		)	(14		)	(224		)
Balance at December 31, 2018	$	3,430		$	455		$	2,333		$	145		$	6,363

____________

Schedule of Acquired Finite-Lived Intangible Assets

The following table presents details of our total acquired intangible assets, both finite- and indefinite-lived:



	December 31, 2018										December 31, 2017
	Gross Amount			Accumulated Amortization			Net Amount			Weighted-Average Useful Life (in Years)	Gross Amount			Accumulated Amortization			Net Amount			Weighted-Average Useful Life (in Years)
	(in millions)										(in millions)
Finite-Lived Intangible Assets
Technology	$	54		$	(15	)	$	39		9	$	65		$	(22	)	$	43		8
Customer relationships⁽¹⁾	1,532			(456		)	1,076			18	1,708			(526		)	1,182			18
Other	17			(2		)	15			8	17			(4		)	13			8
Foreign currency translation adjustment	(149		)	64			(85		)		(111		)	46			(65		)
Total finite-lived intangible assets	$	1,454		$	(409	)	$	1,045			$	1,679		$	(506	)	$	1,173
Indefinite-Lived Intangible Assets
Exchange and clearing registrations	$	1,257		$	—		$	1,257			$	1,257		$	—		$	1,257
Trade names	122			—			122				129			—			129
Licenses	52			—			52				52			—			52
Foreign currency translation adjustment	(176		)	—			(176		)		(143		)	—			(143		)
Total indefinite-lived intangible assets	$	1,255		$	—		$	1,255			$	1,295		$	—		$	1,295
Total intangible assets	$	2,709		$	(409	)	$	2,300			$	2,974		$	(506	)	$	2,468

____________


⁽¹⁾	The decrease in the gross amount and accumulated amortization for customer relationships as of December 31, 2018 compared with 2017 is primarily due to certain intangible assets that became fully amortized in fourth quarter of 2018.

Schedule of Acquired Indefinite-lived Intangible Assets

The following table presents details of our total acquired intangible assets, both finite- and indefinite-lived:



	December 31, 2018										December 31, 2017
	Gross Amount			Accumulated Amortization			Net Amount			Weighted-Average Useful Life (in Years)	Gross Amount			Accumulated Amortization			Net Amount			Weighted-Average Useful Life (in Years)
	(in millions)										(in millions)
Finite-Lived Intangible Assets
Technology	$	54		$	(15	)	$	39		9	$	65		$	(22	)	$	43		8
Customer relationships⁽¹⁾	1,532			(456		)	1,076			18	1,708			(526		)	1,182			18
Other	17			(2		)	15			8	17			(4		)	13			8
Foreign currency translation adjustment	(149		)	64			(85		)		(111		)	46			(65		)
Total finite-lived intangible assets	$	1,454		$	(409	)	$	1,045			$	1,679		$	(506	)	$	1,173
Indefinite-Lived Intangible Assets
Exchange and clearing registrations	$	1,257		$	—		$	1,257			$	1,257		$	—		$	1,257
Trade names	122			—			122				129			—			129
Licenses	52			—			52				52			—			52
Foreign currency translation adjustment	(176		)	—			(176		)		(143		)	—			(143		)
Total indefinite-lived intangible assets	$	1,255		$	—		$	1,255			$	1,295		$	—		$	1,295
Total intangible assets	$	2,709		$	(409	)	$	2,300			$	2,974		$	(506	)	$	2,468

____________


⁽¹⁾	The decrease in the gross amount and accumulated amortization for customer relationships as of December 31, 2018 compared with 2017 is primarily due to certain intangible assets that became fully amortized in fourth quarter of 2018.

Estimated Future Amortization Expense



	(in millions)
2019	$	100
2020	98
2021	97
2022	94
2023	92
2024 and thereafter	649
Total	$	1,130

Schedule of Finite-Lived Intangible Assets [Table Text Block]



	Gross Amount		Accumulated Amortization			Net Amount
	(in millions)
Finite-lived intangible assets reclassified as held for sale - customer relationships	$	21	$	(10	)	$	11
Indefinite-lived intangible assets reclassified as held for sale - trade name	$	5	$	—		$	5
Total intangible assets held for sale	$	26	$	(10	)	$	16

Schedule of Indefinite-Lived Intangible Assets [Table Text Block]



	Gross Amount		Accumulated Amortization			Net Amount
	(in millions)
Finite-lived intangible assets reclassified as held for sale - customer relationships	$	21	$	(10	)	$	11
Indefinite-lived intangible assets reclassified as held for sale - trade name	$	5	$	—		$	5
Total intangible assets held for sale	$	26	$	(10	)	$	16

Deferred Revenue (Tables)

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Changes in Deferred Revenue

The changes in our deferred revenue during the year ended December 31, 2018 are reflected in the following table:



	Initial Listing Revenues			Annual Listings Revenues			Market Technology Revenues			Corporate Solutions and Other Revenues⁽³⁾			Information Services Revenues			Other⁽⁴⁾			Total
	(in millions)
Balance at December 31, 2017	$	64		$	3		$	109		$	37		$	40		$	34		$	287
Additions	29			236			168			242			169			23			867
Revenue recognized	(25		)	(234		)	(183		)	(242		)	(130		)	(36		)	(850		)
Reclassification of deferred revenue⁽¹⁾	—			—			(11		)	11			—			—			—
Deferred revenue reclassified to held for sale⁽²⁾	—			—			—			(12		)	—			—			(12		)
Translation adjustment	(2		)	(1		)	(8		)	—			1			(1		)	(11		)
Balance at December 31, 2018	$	66		$	4		$	75		$	36		$	80		$	20		$	281

____________


⁽¹⁾	Concurrent with the realignment of our BWise internal audit, regulatory compliance management, and operational risk management software solutions from our Market Technology segment to our Corporate Services segment, deferred revenue was reassigned to the Corporate Services segment.

⁽²⁾ See Note 5, “Assets and Liabilities Held for Sale,” for further discussion.


⁽³⁾	Other revenues include the revenues from the Public Relations Solutions and Digital Media Services businesses through the date of sale (April 2018). See “2018 Divestiture,” of Note 3, “Acquisitions and Divestiture,” to the consolidated financial statements for further discussion.


⁽⁴⁾	The balance as of December 31, 2018 and 2017 primarily includes deferred revenue from listing of additional shares fees which are included in our Listing Services segment. The activity during the period primarily pertains to our Trade Management Services and FICC businesses, which are included in our Market Services segment, for contracts paid monthly or quarterly in advance of the service.

Estimated Deferred Revenue

As of December 31, 2018, we estimate that our deferred revenue will be recognized in the following years:



	Initial Listing Revenues		Annual Listings Revenues		Market Technology Revenues		Corporate Solutions Revenues		Information Services Revenues		Other⁽¹⁾		Total
	(in millions)
Fiscal year ended:
2019	$	23	$	4	$	47	$	33	$	77	$	10	$	194
2020	20		—		21		3		3		7		54
2021	10		—		7		—		—		2		19
2022	7		—		—		—		—		1		8
2023	5		—		—		—		—		—		5
2024 and thereafter	1		—		—		—		—		—		1
Total	$	66	$	4	$	75	$	36	$	80	$	20	$	281

____________


⁽¹⁾	Other primarily includes revenues from listing of additional shares fees which are included in our Listing Services business.

Debt Obligations (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Changes in Debt Obligations

The following table presents the changes in the carrying amount of our debt obligations during the year ended December 31, 2018:



	December 31, 2017		Additions		Payments, Accretion and Other			December 31, 2018
Short-term debt:	(in millions)
Commercial paper	$	480	$	4,096	$	(4,301	)	$	275
Senior unsecured floating rate notes due March 22, 2019⁽¹⁾	498		—		2			500
$400 million senior unsecured term loan facility due November 25, 2019 (average interest rate of 3.48% for the period January 1, 2018 through December 31, 2018)⁽²⁾	100		—		—			100
Total short-term debt	1,078		4,096		(4,299		)	875
Long-term debt:
5.55% senior unsecured notes due January 15, 2020	599		—		—			599
3.875% senior unsecured notes due June 7, 2021	716		—		(30		)	686
4.25% senior unsecured notes due June 1, 2024	496		—		1			497
1.75% senior unsecured notes due May 19, 2023	712		—		(30		)	682
3.85% senior unsecured notes due June 30, 2026	496		—		—			496
$1 billion revolving credit commitment due April 25, 2022 (average interest rate of 2.74% for the period January 1, 2018 through December 31, 2018)	110		—		(114		)	(4		)
Total long-term debt	3,129		—		(173		)	2,956
Total debt obligations	$	4,207	$	4,096	$	(4,472	)	$	3,831

____________


⁽¹⁾	Balance was reclassified to short-term debt as of March 31, 2018.


⁽²⁾	Balance was reclassified to short-term debt as of December 31, 2018.

Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Share-Based Compensation Expense



	Year Ended December 31,
	2018			2017			2016
	(in millions)
Share-based compensation expense before income taxes	$	69		$	70		$	86
Income tax benefit	(19		)	(29		)	(35		)
Share-based compensation expense after income taxes	$	50		$	41		$	51

Summary of Restricted Stock Activity

The following table summarizes our restricted stock activity for the years ended December 31, 2018, 2017 and 2016:



	Restricted Stock
	Number of Awards		Weighted-Average Grant Date Fair Value

Unvested balances at December 31, 2015	3,343,738		$	35.36
Granted	724,200		$	62.91
Vested	(1,238,980	)	$	27.91
Forfeited	(268,380	)	$	43.29
Unvested balances at December 31, 2016	2,560,578		$	45.92
Granted	737,864		$	67.48
Vested	(1,102,823	)	$	38.56
Forfeited	(207,119	)	$	52.29
Unvested balances at December 31, 2017	1,988,500		$	57.34
Granted	550,544		$	81.66
Vested	(702,832	)	$	48.64
Forfeited	(252,837	)	$	63.86
Unvested balances at December 31, 2018	1,583,375		$	68.62

Schedule of Weighted-Average Assumptions Used to Determine the Weighted-Average Fair Values

The following weighted-average assumptions were used to determine the weighted-average fair values of the PSU awards granted under the three-year PSU program:



	Year Ended December 31,
	2018		2017
Weighted-average risk free interest rate⁽¹⁾	2.36	%	1.44	%
Expected volatility⁽²⁾	18.7	%	19.2	%
Weighted-average grant date share price	$86.24		$69.45
Weighted-average fair value at grant date	$116.86		$81.57

____________


⁽¹⁾	The risk-free interest rate for periods within the expected life of the award is based on the U.S. Treasury yield curve in effect at the time of grant.


⁽²⁾	We use historic volatility for PSU awards issued under the three-year PSU program, as implied volatility data could not be obtained for all the companies in the peer groups used for relative performance measurement within the program.

Summary of PSU Activity

The following table summarizes our PSU activity for the years ended December 31, 2018, 2017 and 2016:



	PSUs
	One-Year Program				Three-Year Program
	Number of Awards		Weighted-Average Grant Date Fair Value		Number of Awards		Weighted-Average Grant Date Fair Value
Unvested balances at December 31, 2015	423,967		$	41.34	1,439,718		$	49.41
Granted⁽¹⁾	242,642		$	58.33	761,501		$	66.89
Vested	(242,793	)	$	39.63	(879,926	)	$	43.81
Forfeited	(45,050	)	$	47.72	(6,625	)	$	69.11
Unvested balances at December 31, 2016	378,766		$	52.55	1,314,668		$	63.18
Granted⁽¹⁾	197,075		$	65.51	803,712		$	55.57
Vested	(202,073	)	$	49.93	(1,079,925	)	$	42.83
Forfeited	(40,764	)	$	55.92	(28,497	)	$	87.86
Unvested balances at December 31, 2017	333,004		$	61.39	1,009,958		$	78.18
Granted⁽¹⁾	177,831		$	80.97	484,075		$	90.92
Vested	(170,257	)	$	58.49	(655,204	)	$	64.08
Forfeited	(26,347	)	$	61.83	(1,079	)	$	81.57
Unvested balances at December 31, 2018	314,231		$	74.01	837,750		$	96.57

____________


⁽¹⁾	Includes target awards granted and certain additional awards granted based on overachievement of performance parameters.

Summary of Stock Options, Valuation Assumptions

We estimated the fair value of this stock option award using the Black-Scholes valuation model using the following assumptions:



Expected life (in years)	6
Weighted-average risk free interest rate	2.1	%
Expected volatility	25.6	%
Dividend yield	1.92	%

Summary of Stock Option Activity

A summary of stock option activity for the years ended December 31, 2018, 2017 and 2016 is as follows:



	Number of Stock Options		Weighted-Average Exercise Price

Outstanding at December 31, 2015	2,626,487		$	27.74
Exercised	(1,219,820	)	34.00
Forfeited	(296	)	23.31
Outstanding at December 31, 2016	1,406,371		$	22.32
Granted	268,817		66.68
Exercised	(1,102,830	)	21.98
Forfeited	(978	)	21.33
Outstanding at December 31, 2017	571,380		$	43.84
Exercised	(118,094	)	24.44
Forfeited	(5,570	)	25.29
Outstanding at December 31, 2018	447,716		$	49.19
Exercisable at December 31, 2018	268,504		$	37.51

Summary of Significant Ranges of Outstanding and Exercisable Stock

The following table summarizes significant ranges of outstanding and exercisable stock options as of December 31, 2018:



					Outstanding						Exercisable
Range of Exercise Prices					Number of Stock Options	Weighted-Average Remaining Contractual Term (in years)	Weighted-Average Exercise Price		Aggregate Intrinsic Value (in millions)		Number Exercisable	Weighted-Average Remaining Contractual Term (in years)	Weighted-Average Exercise Price		Aggregate Intrinsic Value (in millions)
$	18.67	-	$	20.10	76,844	1.17	$	19.74	$	5	76,844	1.17	$	19.74	$	5
$	25.28	-	$	66.68	370,872	6.42	55.29		10		191,660	4.94	44.64		7
Total					447,716	5.52	$	49.19	$	15	268,504	3.86	$	37.51	$	12

Summary of ESPP

The following table summarizes employee activity and expenses associated with the ESPP for the years ended December 31, 2018, 2017 and 2016.



	Year Ended December 31,
	2018		2017		2016
Number of shares purchased by employees	205,785		235,859		233,464
Weighted-average price of shares purchased	$	66.79	$	58.26	$	50.39
Compensation expenses	$	3	$	3	$	4

Nasdaq Stockholders’ Equity (Tables)

12 Months Ended

Dec. 31, 2018

Equity [Abstract]

Common Stock in Treasury, at Cost

A summary of our share repurchase activity, reported based on settlement date is as follows:



	Year Ended December 31,
	2018		2017

Number of shares of common stock repurchased	4,508,426		2,843,519
Average price paid per share	$	87.43	$	71.56
Total purchase price (in millions)	$	394	$	203

Schedule of Dividends Declared

During 2018, our board of directors declared the following cash dividends:



Declaration Date	Dividend Per Common Share		Record Date	Total Amount Paid		Payment Date
				(in millions)
January 30, 2018	$	0.38	March 16, 2018	$	63	March 30, 2018
March 26, 2018	0.44		June 15, 2018	73		June 29, 2018
July 24, 2018	0.44		September 14, 2018	72		September 28, 2018
October 24, 2018	0.44		December 14, 2018	72		December 28, 2018
				$	280

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of Financial Assets Measured at Fair Value on Recurring Basis



	December 31, 2018
	Total		Level 1		Level 2		Level 3
	(in millions)
Assets at Fair Value
Financial investments, at fair value	$	268	$	133	$	135	$	—
Default fund and margin deposit investments	1,649		327		1,322		—
Total Assets at Fair Value	$	1,917	$	460	$	1,457	$	—
Liabilities at Fair Value
Other financial instruments	$	112	$	—	$	112	$	—
Total Liabilities at Fair Value	$	112	$	—	$	112	$	—



	December 31, 2017
	Total		Level 1		Level 2		Level 3
	(in millions)
Assets at Fair Value
Financial investments, at fair value	$	235	$	135	$	100	$	—
Default fund and margin deposit investments	2,129		371		1,758		—
Total Assets at Fair Value	$	2,364	$	506	$	1,858	$	—

Clearing Operations (Tables)

12 Months Ended

Dec. 31, 2018

Due to and from Broker-Dealers and Clearing Organizations [Abstract]

Schedule of Clearing Member Default Fund Contributions

As of December 31, 2018, clearing member default fund contributions and margin deposits were as follows:



	December 31, 2018
	Cash Contributions		Non-Cash Contributions		Total Contributions
	(in millions)
Default fund contributions	$	370	$	129	$	499
Margin deposits	4,372		3,073		7,445
Total	$	4,742	$	3,202	$	7,944

Schedule of Derivative Contracts Outstanding

The following table includes the market value of derivative contracts outstanding prior to netting:



	December 31, 2018
	(in millions)
Commodity and seafood options, futures and forwards^(1)(2)(3)	$	1,196
Fixed-income options and futures⁽¹⁾⁽²⁾	600
Stock options and futures⁽¹⁾⁽²⁾	271
Index options and futures⁽¹⁾⁽²⁾	135
Total	$	2,202

____________


⁽¹⁾	We determined the fair value of our option contracts using standard valuation models that were based on market-based observable inputs including implied volatility, interest rates and the spot price of the underlying instrument.


⁽²⁾	We determined the fair value of our futures contracts based upon quoted market prices and average quoted market yields.


⁽³⁾	We determined the fair value of our forward contracts using standard valuation models that were based on market-based observable inputs including LIBOR rates and the spot price of the underlying instrument.

Schedule of Derivative Contracts Cleared

The following table includes the total number of derivative contracts cleared through Nasdaq Clearing for the years ended December 31, 2018 and 2017:



	December 31, 2018	December 31, 2017
Commodity and seafood options, futures and forwards⁽¹⁾	1,649,912	2,824,188
Fixed-income options and futures	22,839,794	20,376,383
Stock options and futures	24,978,684	26,023,816
Index options and futures	49,038,297	44,928,284
Total	98,506,687	94,152,671

____________


(1)	The total volume in cleared power related to commodity contracts was 1,067 Terawatt hours (TWh) for the year ended December 31, 2018 and 1,199 TWh for the year ended December 31, 2017.

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

+ References

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+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Domestic and Foreign Components of Income Before Income Tax Provision

The following table presents the domestic and foreign components of income (loss) before income tax provision:



	Year Ended December 31,
	2018		2017		2016
	(in millions)
Domestic	$	636	$	556	$	(153	)
Foreign	428		316		286
Income before income tax provision	$	1,064	$	872	$	133

Schedule of Components of Income Tax Expense (Benefit)

The income tax provision consists of the following amounts:



	Year Ended December 31,
	2018		2017			2016
Current income tax provision:	(in millions)
Federal	$	103	$	51		$	37
State	56		17			21
Foreign	146		68			106
Total current income tax provision	305		136			164
Deferred income tax provision (benefit):
Federal	185		(16		)	(98		)
State	116		24			(35		)
Foreign	—		(1		)	(4		)
Total deferred income provision (benefit)	301		7			(137		)
Total income tax provision	$	606	$	143		$	27

Reconciliation of Provision of Income Taxes

A reconciliation of the income tax provision, based on the U.S. federal statutory rate, to our actual income tax provision for the years ended December 31, 2018, 2017 and 2016 is as follows:



	Year Ended December 31,
	2018		2017		2016
Federal income tax provision at the statutory rate	21.0	%	35.0	%	35.0	%
State income tax provision, net of federal effect	3.7	%	2.6	%	(6.7	)%
Change in deferred taxes due to change in law	27.0	%	(9.9	)%	(1.2	)%
Excess tax benefits related to employee share-based compensation	(0.7	)%	(4.0	)%	—	%
Non-U.S. subsidiary earnings	0.1	%	(6.0	)%	(7.3	)%
Tax credits and deductions	(0.2	)%	(1.0	)%	(5.1	)%
Change in unrecognized tax benefits	4.7	%	(0.8	)%	4.2	%
Other, net	1.4	%	0.5	%	1.4	%
Actual income tax provision	57.0	%	16.4	%	20.3	%

Schedule of Deferred Tax Assets and Liabilities

The temporary differences, which give rise to our deferred tax assets and (liabilities), consisted of the following:



	December 31,
	2018			2017
Deferred tax assets:	(in millions)
Deferred revenues	$	19		$	25
U.S. federal net operating loss	—			1
Foreign net operating loss	23			30
State net operating loss	4			4
Compensation and benefits	33			42
Foreign currency translation	—			292
Tax credits	—			7
Federal benefit of uncertain tax positions	17			—
Other	25			20
Gross deferred tax assets	121			421
Less: valuation allowance	(23		)	(30		)
Total deferred tax assets, net of valuation allowance	$	98		$	391

Deferred tax liabilities:
Amortization of software development costs and depreciation	$	(41	)	$	(47	)
Amortization of acquired intangible assets	(498		)	(510		)
Investments	(34		)	(26		)
Other	(22		)	(19		)
Gross deferred tax liabilities	(595		)	(602		)
Net deferred tax liabilities	$	(497	)	$	(211	)
Reported as:
Non-current deferred tax assets⁽¹⁾	4			14
Deferred tax liabilities, net	(501		)	(225		)
Net deferred tax liabilities	$	(497	)	$	(211	)

____________


⁽¹⁾	Included in other non-current assets in the Consolidated Balance Sheets.

Summary of Net Operating Losses and Credits

As of December 31, 2018, the expiration dates for the NOLs are as follows:



Jurisdiction	Amount		Expiration Date
	(in millions)
Foreign NOL	$	3	2019-2025
Foreign NOL	20		No expiration date
State NOL	4		2025-2036

Summary of Tax Credit Carryforwards

As of December 31, 2018, the expiration dates for the NOLs are as follows:



Jurisdiction	Amount		Expiration Date
	(in millions)
Foreign NOL	$	3	2019-2025
Foreign NOL	20		No expiration date
State NOL	4		2025-2036

Reconciliation of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:



	Year Ended December 31,
	2018			2017			2016
	(in millions)
Beginning balance	$	45		$	48		$	40
Additions as a result of tax positions taken in prior periods	28			2			9
Additions as a result of tax positions taken in the current period	6			5			3
Reductions related to settlements with taxing authorities	(23		)	—			(4		)
Reductions as a result of lapses of the applicable statute of limitations	(4		)	(10		)	—
Ending balance	$	52		$	45		$	48

Business Segments (Tables)

12 Months Ended

Dec. 31, 2018

Segment Reporting [Abstract]

Schedule of Operating Segments

The following table presents certain information regarding our operating segments for the years ended December 31, 2018, 2017 and 2016:



	Market Services			Corporate Services		Information Services		Market Technology		Corporate Items			Consolidated
	(in millions)
Year Ended December 31, 2018
Total revenues	$	2,709		$	528	$	714	$	270	$	56		$	4,277
Transaction-based expenses	(1,751		)	—		—		—		—			(1,751		)
Revenues less transaction-based expenses	958			528		714		270		56			2,526
Depreciation and amortization	95			41		51		$	21	2			210
Operating income (loss)	544			163		460		34		(173		)	1,028
Total assets	10,299			734		3,352		467		848			15,700
Purchase of property and equipment	28			29		17		37		—			111
Year Ended December 31, 2017
Total revenues	$	2,418		$	501	$	588	$	247	$	194		$	3,948
Transaction-based expenses	(1,537		)	—		—		—		—			(1,537		)
Revenues less transaction-based expenses	881			501		588		247		194			2,411
Depreciation and amortization	95			44		26		14		9			188
Operating income (loss)	481			158		418		57		(123		)	991
Total assets	9,471			865		3,420		572		1,026			15,354
Purchase of property and equipment	59			41		10		34		—			144
Year Ended December 31, 2016
Total revenues	$	2,255		$	477	$	540	$	241	$	191		$	3,704
Transaction-based expenses	(1,428		)	—		—		—		—			(1,428		)
Revenues less transaction-based expenses	827			477		540		241		191			2,276
Depreciation and amortization	87			42		18		13		10			170
Operating income (loss)	450			130		383		73		(200		)	836
Total assets	8,626			1,263		2,439		497		586			13,411
Purchase of property and equipment	62			37		8		27		—			134

Schedule of Corporate Items

A summary of our corporate items is as follows:



	Year Ended December 31,
	2018			2017			2016
	(in millions)
Revenues - divested businesses	$	56		$	194		$	191
Expenses:
Amortization expense of acquired intangible assets	109			92			82
Merger and strategic initiatives expense	21			44			76
Clearing default	31			—			—
Extinguishment of debt	—			10			—
Restructuring charges	—			—			41
Regulatory matter	—			—			6
Expenses - divested businesses	51			167			168
Executive compensation	—			—			12
Other	17			4			6
Total expenses	229			317			391
Operating loss	$	(173	)	$	(123	)	$	(200	)

Revenue from External Customers by Geographic Areas



	Total Revenues		Property and Equipment, Net
2018:	(in millions)
United States	$	3,379	$	224
All other countries	898		152
Total	$	4,277	$	376
2017:
United States	$	3,081	$	247
All other countries	867		153
Total	$	3,948	$	400
2016:
United States	$	2,679	$	244
All other countries	1,025		118
Total	$	3,704	$	362

Organization and Nature of Operations (Details) fund in Thousands, $ in Billions	12 Months Ended
	Dec. 31, 2018 USD ($) marketplace segment fund company exchange exchange_traded_product country
Organization And Basis Of Presentation [Line Items]
Number of operating segments \| segment	4
Number of funds and other investment vehicles \| fund	35
Market Services
Organization And Basis Of Presentation [Line Items]
Number of derivative exchanges listing commodities offerings \| exchange	2
Market Services \| United States \| Options Markets
Organization And Basis Of Presentation [Line Items]
Number of exchanges \| exchange	6
Market Services \| United States \| Cash Equities Trading Markets
Organization And Basis Of Presentation [Line Items]
Number of exchanges \| exchange	3
Corporate Services
Organization And Basis Of Presentation [Line Items]
Total number of listings on The Nasdaq Stock Market \| company	3,058
ETPs and other listings listed on Nasdaq Stock Market \| company	392
Approximate combined market capitalization, U.S. \| $	$ 11,100
Total number of listed companies within Nordic and Baltic exchanges \| company	1,019
Approximate combined market capitalization within Nordic and Baltic exchanges \| $	$ 1,300
Information Services
Organization And Basis Of Presentation [Line Items]
Number of exchange traded products licensed to Nasdaq's Indexes \| exchange_traded_product	365
Assets management value \| $	$ 172
Market Technology
Organization And Basis Of Presentation [Line Items]
Number of exchanges \| marketplace	100
Number of countries services are provided \| country	50

Summary of Significant Accounting Policies (Narrative) (Details)		12 Months Ended
	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($) agreement	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Cash and cash equivalents		$ 545,000,000	$ 377,000,000
Restricted cash and cash equivalents, current		41,000,000	22,000,000
Allowance for doubtful accounts		13,000,000	9,000,000	$ 13,000,000
Equity security impairment loss		0	0	0
Goodwill, impairment loss		0	0	0
Non-cash write-off related to indefinite-lived intangible asset		0	0	0
Asset impairment charges		0	9,000,000	8,000,000
Elimination of operating sublease income		$ (5,000,000)	$ (3,000,000)	$ (4,000,000)
Trade management services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction		12 months
United States \| Listing services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction		12 months
Europe \| Listing services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction		12 months
Corporate Services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Number of types of license agreements \| agreement		2
Minimum \| Listing services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction		2 years
Maximum \| Listing services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction		6 years
Services transferred at a point in time \| Market Services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognized (percentage)		63.60%	62.70%	63.40%
Services transferred over time \| Market Services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognized (percentage)		36.40%	37.30%	36.60%
Rebranding of trade name
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Non-cash write-off related to indefinite-lived intangible asset				$ 578,000,000
Computer Software, Intangible Asset \| Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of intangible assets		3 years
Computer Software, Intangible Asset \| Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of intangible assets		5 years
Other
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Non-cash write-off related to indefinite-lived intangible asset				0
Employee Stock Purchase Plan
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percentage of fair market value of common stock		85.00%
Percentage of discount to employees on purchase of common stock under employee stock purchase plant		15.00%
Cash Equivalents
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Cash and cash equivalents		$ 198,000,000	$ 183,000,000
Order Machine
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Impairment charge				$ 7,000,000
Building and Building Improvements \| Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of property and equipment		10 years
Building and Building Improvements \| Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of property and equipment		40 years
Data processing equipment and software \| Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of property and equipment		2 years
Data processing equipment and software \| Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of property and equipment		5 years
Furniture And Equipment \| Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of property and equipment		5 years
Furniture And Equipment \| Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Estimated useful life of property and equipment		10 years
Subsequent Event
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Net lease assets	$ 442,000,000
Lease liabilities	483,000,000
Accounting Standards Update 2016-02 \| Subsequent Event
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Elimination of operating sublease income	$ 41,000,000

Summary of Significant Accounting Policies (Adjustments to Reflect Adoption of Topic 606) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues:
Total revenues	$ 4,277	$ 3,948	$ 3,704
Total operating expenses	1,498	1,420	1,440
Income before income taxes	1,064	872	133
Income tax provision	606	143	27
Net income attributable to Nasdaq	$ 458	$ 729	$ 106
Diluted earnings per share (in dollars per share)	$ 2.73	$ 4.30	$ 0.63
Assets
Other current assets	$ 390	$ 532
Other non-current assets	291	390
Deferred tax assets	121	421
Total assets	15,700	15,354	$ 13,411
Liabilities
Deferred revenue	194	161
Non-current deferred revenue	87	126
Total liabilities	10,251	9,474
Nasdaq stockholders’ equity:
Retained earnings	4,558	3,963
Total Nasdaq stockholders' equity	5,449	5,880
Total liabilities and equity	15,700	15,354
Market Services
Revenues:
Total revenues	2,709	2,418	2,255
Corporate Services
Revenues:
Total revenues	528	501	477
Information Services
Revenues:
Total revenues	714	588	540
Market Technology
Revenues:
Total revenues	$ 270	247	241
Accounting Standards Update 2014-09 \| Restatement Adjustment
Revenues:
Total revenues		(17)	(1)
Total operating expenses		(9)	2
Income before income taxes		(8)	(3)
Income tax provision		(3)	(1)
Net income attributable to Nasdaq		$ (5)	$ (2)
Diluted earnings per share (in dollars per share)		$ (0.03)	$ (0.01)
Assets
Other current assets		$ (19)	$ (15)
Other non-current assets		(38)	(46)
Deferred tax assets		2	(1)
Total assets		(55)	(62)
Liabilities
Deferred revenue		(28)	(24)
Non-current deferred revenue		(20)	(36)
Total liabilities		(48)	(60)
Nasdaq stockholders’ equity:
Retained earnings		(7)	(2)
Total Nasdaq stockholders' equity		(7)	(2)
Total liabilities and equity		(55)	(62)
Accounting Standards Update 2014-09 \| Restatement Adjustment \| Market Services
Revenues:
Total revenues		0	0
Accounting Standards Update 2014-09 \| Restatement Adjustment \| Corporate Services
Revenues:
Total revenues		(3)	(3)
Accounting Standards Update 2014-09 \| Restatement Adjustment \| Information Services
Revenues:
Total revenues		0	0
Accounting Standards Update 2014-09 \| Restatement Adjustment \| Market Technology
Revenues:
Total revenues		$ (14)	$ 2

Summary of Significant Accounting Policies (Remaining Performance Obligation) (Details) - Market Technology $ in Millions	Dec. 31, 2018 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 255
Revenue, remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 183
Revenue, remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 94
Revenue, remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 58
Revenue, remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 30
Revenue, remaining performance obligation, expected timing of satisfaction	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 695
Revenue, remaining performance obligation, expected timing of satisfaction

Acquisitions and Divestiture (2019 Acquisition) (Details) - Cinnober $ in Millions	1 Months Ended
	Feb. 22, 2019	Dec. 31, 2018 kr / shares	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
SEK per share offering (in SEK per share)		kr 87
SEK per warrant offering (in SEK per warrant)		kr 121
Payments to acquire businesses \| $			$ 220
Scenario, Forecast
Business Acquisition [Line Items]
Ownership percentage before transaction	99.60%
Ownership percentage after transaction	100.00%

Acquisitions and Divestiture (2018 Divestiture) (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gain on divestiture of businesses			$ 33	$ 0	$ 0
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Public Relations Solutions and Digital Media Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gain on divestiture of businesses		$ 33
Gain on divestiture of business, after tax		$ 14
Working capital adjustment	$ 8
Working capital adjustment, after tax	$ 5

Acquisitions and Divestiture (2017 Acquisitions) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Oct. 31, 2018
Business Acquisition [Line Items]
Purchase Consideration		$ 101	$ 778	$ 1,466
Goodwill		$ 6,363	$ 6,586
eVestment
Business Acquisition [Line Items]
Purchase Consideration	$ 744
Total Net Liabilities Acquired	10				$ (10)
Total Net Deferred Tax Liability	(104)				(96)
Acquired Intangible Assets	405				405
Goodwill					$ 445
Purchase price	705
Acquisition of businesses, net of cash and cash equivalents acquired	22
Purchase price allocation deferred tax assets	39
Purchase price allocation deferred tax liabilities	$ 143

Acquisitions and Divestiture (2016 Acquisitions) (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		12 Months Ended
	May 31, 2016	Feb. 29, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Goodwill					$ 6,363	$ 6,586
Proceeds from long-term debt issuances, net of debt issuance costs					$ 0	648	$ 2,456
ISE
Business Acquisition [Line Items]
Cash consideration				$ 1,070
Total Net Liabilities Acquired				83
Total Net Deferred Tax Liability				(185)
Acquired Intangible Assets, Indefinite-lived							623
Goodwill							549
Purchase price allocation deferred tax liabilities				266
Purchase price allocation deferred tax assets				81
Boardvantage
Business Acquisition [Line Items]
Cash consideration	$ 242
Total Net Liabilities Acquired	28
Total Net Deferred Tax Liability	(45)					(38)
Intangible assets, finite-lived							111
Goodwill						$ 141
Measurement period adjustment, financial liabilities			$ 7
Purchase price allocation deferred tax liabilities	46
Purchase price allocation deferred tax assets	1
Payments to acquire businesses	197
Cost of acquired entity working capital adjustments	45
Marketwired
Business Acquisition [Line Items]
Cash consideration		$ 111
Total Net Liabilities Acquired							(1)
Total Net Deferred Tax Liability							(5)
Intangible assets, finite-lived							31
Goodwill							86
Measurement period adjustment related to acquisition				$ 5
Purchase price allocation deferred tax liabilities		10
Payments to acquire businesses		109
Cost of acquired entity working capital adjustments		2
Nasdaq Canada
Business Acquisition [Line Items]
Cash consideration		116
Total Net Liabilities Acquired		6
Total Net Deferred Tax Liability		(20)
Intangible assets, finite-lived							76
Goodwill							$ 54
Payments to acquire businesses		115
Cost of acquired entity working capital adjustments		1
Revolving Credit Facility \| Boardvantage
Business Acquisition [Line Items]
Proceeds from long-term debt issuances, net of debt issuance costs	$ 197
Revolving Credit Facility \| Marketwired
Business Acquisition [Line Items]
Proceeds from long-term debt issuances, net of debt issuance costs		109
Revolving Credit Facility \| Nasdaq Canada
Business Acquisition [Line Items]
Proceeds from long-term debt issuances, net of debt issuance costs		$ 55

Acquisitions and Divestiture (Intangible Assets) (Details) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2017 USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016 USD ($)	Oct. 31, 2018 USD ($)
eVestment
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived	$ 405				$ 405
eVestment \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived	$ 378
Estimated average useful life	14 years
Amortization period of intangible assets for tax purposes		15 years
eVestment \| Trade name
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived	$ 13
Estimated average useful life	8 years		8 years
eVestment \| Technology
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived	$ 14
Estimated average useful life	8 years		8 years
eVestment \| Discount rate used \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used	0.093
eVestment \| Discount rate used \| Trade name
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used	0.092
eVestment \| Discount rate used \| Technology
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used	0.092
ISE
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Identifiable assets acquired				$ 623
ISE \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 148
Estimated average useful life				13 years
ISE \| Discount rate used \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.091
Boardvantage
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 111
Boardvantage \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 103
Estimated average useful life				14 years
Boardvantage \| Trade name
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 2
Estimated average useful life				1 year
Boardvantage \| Technology
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 6
Estimated average useful life				5 years
Boardvantage \| Discount rate used \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.155
Boardvantage \| Discount rate used \| Trade name
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.150
Boardvantage \| Discount rate used \| Technology
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.155
Marketwired
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 31
Marketwired \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 29
Estimated average useful life				6 years
Marketwired \| Trade name
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 2
Estimated average useful life				2 years
Marketwired \| Discount rate used \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.164
Marketwired \| Discount rate used \| Trade name
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.158
Nasdaq Canada
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 76
Nasdaq Canada \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, finite-lived				$ 76
Estimated average useful life				17 years
Nasdaq Canada \| Discount rate used \| Customer relationships
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.103
Licenses \| ISE
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, indefinite-lived				$ 467
Licenses \| ISE \| Discount rate used
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.086
Trade name \| ISE
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, indefinite-lived				$ 8
Trade name \| ISE \| Discount rate used
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Discount rate used				0.086

Assets and Liabilities Held For Sale (Details) - USD ($)	1 Months Ended	12 Months Ended
	Apr. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charge	$ 0	$ 0
Carrying Amount of Assets and Liabilities Held for Sale [Abstract]
Deferred revenue		194,000,000	$ 161,000,000
Public Relations Solutions and Digital Media Services \| Disposal Group, Not Discontinued Operations
Carrying Amount of Assets and Liabilities Held for Sale [Abstract]
Receivables, net		13,000,000	27,000,000
Property and equipment, net		10,000,000	21,000,000
Goodwill		47,000,000	202,000,000
Intangible assets, net		16,000,000	38,000,000
Other assets		3,000,000	9,000,000
Total assets held for sale		89,000,000	297,000,000
Deferred tax liabilities		4,000,000	16,000,000
Deferred revenue		12,000,000	2,000,000
Other current liabilities		4,000,000	27,000,000
Total liabilities held for sale		$ 20,000,000	$ 45,000,000

Goodwill and Acquired Intangible Assets (Schedule of Changes in Goodwill) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2018	Dec. 31, 2018
Goodwill [Roll Forward]
Balance at beginning of period		$ 6,586
Goodwill acquired		56
Measurement period adjustment		(8)
Reclassification of goodwill		0
Goodwill reclassified to held for sale		(47)
Foreign currency translation adjustment		(224)
Balance at end of period		6,363
Market Services
Goodwill [Roll Forward]
Balance at beginning of period		3,546
Goodwill acquired		0
Measurement period adjustment		0
Reclassification of goodwill		0
Goodwill reclassified to held for sale		0
Foreign currency translation adjustment		(116)
Balance at end of period		3,430
Corporate Services
Goodwill [Roll Forward]
Balance at beginning of period		490
Goodwill acquired		0
Measurement period adjustment		0
Reclassification of goodwill		29
Goodwill reclassified to held for sale		(47)
Foreign currency translation adjustment		(17)
Balance at end of period		455
Information Services
Goodwill [Roll Forward]
Balance at beginning of period		2,362
Goodwill acquired		56
Measurement period adjustment	$ 8	(8)
Reclassification of goodwill		0
Goodwill reclassified to held for sale		0
Foreign currency translation adjustment		(77)
Balance at end of period		2,333
Market Technology
Goodwill [Roll Forward]
Balance at beginning of period		188
Goodwill acquired		0
Measurement period adjustment		0
Reclassification of goodwill		(29)
Goodwill reclassified to held for sale		0
Foreign currency translation adjustment		(14)
Balance at end of period		$ 145

Goodwill and Acquired Intangible Assets (Narrative) (Details) - USD ($)	1 Months Ended		12 Months Ended
	Oct. 31, 2018	Apr. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Indefinite-lived Intangible Assets [Line Items]
Measurement period adjustment			$ (8,000,000)
Amount of goodwill expected to be deductible for tax purposes			807,000,000
Goodwill, impairment loss			0	$ 0	$ 0
Non-cash write-off related to indefinite-lived intangible asset			0	0	0
Amortization expense of acquired intangible assets			109,000,000	92,000,000	$ 82,000,000
Foreign currency translation amortization expense			1,045,000,000	1,173,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Public Relations Solutions and Digital Media Services \| Trade name
Indefinite-lived Intangible Assets [Line Items]
Non-cash write-off related to indefinite-lived intangible asset		$ 2,000,000
Foreign currency translation adjustment
Indefinite-lived Intangible Assets [Line Items]
Foreign currency translation amortization expense			(85,000,000)	$ (65,000,000)
Information Services
Indefinite-lived Intangible Assets [Line Items]
Measurement period adjustment	$ 8,000,000		$ (8,000,000)

Goodwill and Acquired Intangible Assets (Finite-Lived and Indefinite-Lived Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 1,454	$ 1,679
Accumulated Amortization	(409)	(506)
Net Amount	1,045	1,173
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	1,255	1,295
Total intangible assets	2,709	2,974
Intangible assets, net	2,300	2,468
Exchange and clearing registrations
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	1,257	1,257
Trade name
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	122	129
Licenses
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	52	52
Foreign currency translation adjustment
Indefinite-lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	(176)	(143)
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Amount	54	65
Accumulated Amortization	(15)	(22)
Net Amount	$ 39	$ 43
Weighted-Average Useful Life	9 years	8 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 1,532	$ 1,708
Accumulated Amortization	(456)	(526)
Net Amount	$ 1,076	$ 1,182
Weighted-Average Useful Life	18 years	18 years
Other
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 17	$ 17
Accumulated Amortization	(2)	(4)
Net Amount	$ 15	$ 13
Weighted-Average Useful Life	8 years	8 years
Foreign currency translation adjustment
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ (149)	$ (111)
Accumulated Amortization	64	46
Net Amount	$ (85)	$ (65)

Goodwill and Acquired Intangible Assets (Estimated Future Amortization Expense) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2019	$ 100
2020	98
2021	97
2022	94
2023	92
2024 and thereafter	649
Total	$ 1,130

Goodwill and Acquired Intangible Assets (Finite and Indefinite-Lived Intangible Assets Held-For-Sale) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets reclassified as held for sale - customer relationships, Gross Amount	$ 1,454	$ 1,679
Finite-lived intangible assets reclassified as held for sale - customer relationships, Accumulated Amortization	(409)	(506)
Finite-lived intangible assets reclassified as held for sale - customer relationships, Net Amount	1,045	1,173
Indefinite-lived intangible assets reclassified as held for sale - trade name, Gross Amount	1,255	1,295
Intangible Assets, Gross (Excluding Goodwill)	2,709	2,974
Total intangible assets held for sale, Net Amount	2,300	2,468
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets reclassified as held for sale - customer relationships, Gross Amount	1,532	1,708
Finite-lived intangible assets reclassified as held for sale - customer relationships, Accumulated Amortization	(456)	(526)
Finite-lived intangible assets reclassified as held for sale - customer relationships, Net Amount	1,076	1,182
Trade name
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets reclassified as held for sale - trade name, Gross Amount	122	$ 129
Disposal Group, Not Discontinued Operations \| Public Relations Solutions and Digital Media Services
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, Gross (Excluding Goodwill)	26
Total intangible assets held for sale, Net Amount	16
Disposal Group, Not Discontinued Operations \| Public Relations Solutions and Digital Media Services \| Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets reclassified as held for sale - customer relationships, Gross Amount	21
Finite-lived intangible assets reclassified as held for sale - customer relationships, Accumulated Amortization	(10)
Finite-lived intangible assets reclassified as held for sale - customer relationships, Net Amount	11
Disposal Group, Not Discontinued Operations \| Public Relations Solutions and Digital Media Services \| Trade name
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets reclassified as held for sale - trade name, Gross Amount	5
Indefinite-lived intangible assets reclassified as held for sale - trade name, Net Amount	$ 5

Investments (Schedule of Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Trading securities	$ 259	$ 221
Available-for-sale investment securities	9	14
Financial investments, at fair value	268	235
Equity method investments	135	131
Equity securities	$ 44	$ 152

Investments (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Mar. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2014
Investments, Debt and Securities [Line Items]
Trading securities	$ 259		$ 259	$ 221
Gains and losses on available-for-sale investment securities			0	0
Net income from unconsolidated investees			18	15	$ 2
Proceeds from sale of investment security			169	0	0
Gain on sale of equity investment, pre-tax	118
Gain on sale of equity investment, after tax	93
Equity securities	$ 44		$ 44	152
OCC
Investments, Debt and Securities [Line Items]
Ownership percentage	40.00%		40.00%
Committed equity contribution		$ 150
Capital contribution		$ 30
Annual dividend from shareholders percentage		50.00%
Shares owned (in shares)	2		2
Annual dividend received			$ 13	$ 10	$ 4
Borsa Istanbul Cost Method Investment
Investments, Debt and Securities [Line Items]
Ownership percentage				5.00%
Equity securities							$ 75
Consideration received for put option exercised	$ 45		45
Foreign Government Debt Securities
Investments, Debt and Securities [Line Items]
Trading securities	166		$ 166	$ 160
LCH
Investments, Debt and Securities [Line Items]
Ownership percentage				5.00%
Proceeds from sale of investment security	$ 169
ISE \| OCC
Investments, Debt and Securities [Line Items]
Additional ownership percentage						20.00%
Ownership percentage						40.00%

Property and Equipment, net (Schedule of Property and Equipment, Net) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 800	$ 905
Less: accumulated depreciation and amortization	(424)	(505)
Total property and equipment, net	376	400	$ 362
Data processing equipment and software
Property, Plant and Equipment [Line Items]
Total property and equipment	526	626
Furniture, equipment and leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 274	$ 279

Property and Equipment, net (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 101	$ 96	$ 88
Asset impairment charges	$ 0	$ 9	$ 8

Deferred Revenue (Changes in Deferred Revenue) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	$ 287
Additions	867
Revenue recognized	(850)
Reclassification of deferred revenue	0
Deferred revenue reclassified to held for sale(2)	(12)
Translation adjustment	(11)
Ending balance	281
Initial Listing Revenues
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	64
Additions	29
Revenue recognized	(25)
Reclassification of deferred revenue	0
Deferred revenue reclassified to held for sale(2)	0
Translation adjustment	(2)
Ending balance	66
Annual Listings Revenues
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	3
Additions	236
Revenue recognized	(234)
Reclassification of deferred revenue	0
Deferred revenue reclassified to held for sale(2)	0
Translation adjustment	(1)
Ending balance	4
Market Technology Revenues
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	109
Additions	168
Revenue recognized	(183)
Reclassification of deferred revenue	(11)
Deferred revenue reclassified to held for sale(2)	0
Translation adjustment	(8)
Ending balance	75
Corporate Solutions and Other Revenues
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	37
Additions	242
Revenue recognized	(242)
Reclassification of deferred revenue	11
Deferred revenue reclassified to held for sale(2)	(12)
Translation adjustment	0
Ending balance	36
Information Services Revenues
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	40
Additions	169
Revenue recognized	(130)
Reclassification of deferred revenue	0
Deferred revenue reclassified to held for sale(2)	0
Translation adjustment	1
Ending balance	80
Other
Change in Contract with Customer Liability [Roll Forward]
Beginning balance	34
Additions	23
Revenue recognized	(36)
Reclassification of deferred revenue	0
Deferred revenue reclassified to held for sale(2)	0
Translation adjustment	(1)
Ending balance	$ 20

Deferred Revenue (Estimated Deferred Revenue) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Fiscal year ended:
2019	$ 194
2020	54
2021	19
2022	8
2023	5
2024 and thereafter	1
Total	281	$ 287
Initial Listing Revenues
Fiscal year ended:
2019	23
2020	20
2021	10
2022	7
2023	5
2024 and thereafter	1
Total	66	64
Annual Listings Revenues
Fiscal year ended:
2019	4
2020	0
2021	0
2022	0
2023	0
2024 and thereafter	0
Total	4	3
Market Technology Revenues
Fiscal year ended:
2019	47
2020	21
2021	7
2022	0
2023	0
2024 and thereafter	0
Total	75	109
Corporate Solutions Revenues
Fiscal year ended:
2019	33
2020	3
2021	0
2022	0
2023	0
2024 and thereafter	0
Total	36
Information Services Revenues
Fiscal year ended:
2019	77
2020	3
2021	0
2022	0
2023	0
2024 and thereafter	0
Total	80	40
Other
Fiscal year ended:
2019	10
2020	7
2021	2
2022	1
2023	0
2024 and thereafter	0
Total	$ 20	$ 34

Debt Obligations (Changes in Debt Obligations) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Apr. 30, 2017	Jun. 30, 2016	May 31, 2016	May 31, 2014	Jun. 30, 2013	Jan. 31, 2010
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	$ 1,078,000,000
Additions	4,096,000,000
Payments, Accretion and Other	(4,299,000,000)
Short-term debt - commercial paper ending balance	875,000,000
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	3,129,000,000
Additions	0
Payments, Accretion and Other	(173,000,000)
Long-term debt obligations at end of period	2,956,000,000
Changes In Debt Obligations [Roll Forward]
Total debt obligations at beginning of period	4,207,000,000
Additions	4,096,000,000
Payments, Accretion and Other	(4,472,000,000)
Total debt obligations at end of period	$ 3,831,000,000
Senior Notes \| 5.55% senior unsecured notes due January 15, 2020
Schedule of Debt [Line Items]
Stated rate	5.55%						5.55%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 599,000,000
Additions	0
Payments, Accretion and Other	0
Long-term debt obligations at end of period	$ 599,000,000
Senior Notes \| 3.875% senior unsecured notes due June 7, 2021
Schedule of Debt [Line Items]
Stated rate	3.875%					3.875%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 716,000,000
Additions	0
Payments, Accretion and Other	(30,000,000)
Long-term debt obligations at end of period	$ 686,000,000
Senior Notes \| 4.25% senior unsecured notes due June 1, 2024
Schedule of Debt [Line Items]
Stated rate	4.25%				4.25%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 496,000,000
Additions	0
Payments, Accretion and Other	1,000,000
Long-term debt obligations at end of period	$ 497,000,000
Senior Notes \| 1.75% senior unsecured notes due May 19, 2023
Schedule of Debt [Line Items]
Stated rate	1.75%			1.75%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 712,000,000
Additions	0
Payments, Accretion and Other	(30,000,000)
Long-term debt obligations at end of period	$ 682,000,000
Senior Notes \| 3.85% senior unsecured notes due June 30, 2026
Schedule of Debt [Line Items]
Stated rate	3.85%		3.85%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 496,000,000
Additions	0
Payments, Accretion and Other	0
Long-term debt obligations at end of period	496,000,000
Revolving Credit Facility \| $1 billion revolving credit commitment due April 25, 2022 (average interest rate of 2.74% for the period January 1, 2018 through December 31, 2018)
Schedule of Debt [Line Items]
Facility borrowing capacity	$ 1,000,000,000	$ 1,000,000,000
Interest rate	2.74%
Changes in Long-Term Debt Obligations [Roll Forward]
Long-term debt obligations at beginning of period	$ 110,000,000
Additions	0
Payments, Accretion and Other	(114,000,000)
Long-term debt obligations at end of period	(4,000,000)
Commercial paper
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	480,000,000
Additions	4,096,000,000
Payments, Accretion and Other	(4,301,000,000)
Short-term debt - commercial paper ending balance	275,000,000
Senior unsecured floating rate notes due March 22, 2019
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	498,000,000
Additions	0
Payments, Accretion and Other	2,000,000
Short-term debt - commercial paper ending balance	500,000,000
$400 million senior unsecured term loan facility due November 25, 2019 (average interest rate of 3.48% for the period January 1, 2018 through December 31, 2018)(2)
Schedule of Debt [Line Items]
Facility borrowing capacity	$ 400,000,000
Interest rate	3.48%
Changes In Short-Term Debt Obligations [Roll Forward]
Short-term debt - commercial paper beginning balance	$ 100,000,000
Additions	0
Payments, Accretion and Other	0
Short-term debt - commercial paper ending balance	$ 100,000,000

Debt Obligations (Commercial Paper) (Details) - Commercial paper	12 Months Ended
	Dec. 31, 2018
Short-term Debt [Line Items]
Weighted average interest rate	3.03%
Minimum
Short-term Debt [Line Items]
Maturity period	24 days
Maximum
Short-term Debt [Line Items]
Maturity period	67 days
Weighted Average
Short-term Debt [Line Items]
Maturity period	33 days

Debt Obligations (Senior Unsecured Floating Rate Notes) (Details) - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Short-term Debt		$ 875	$ 1,078
Senior unsecured floating rate notes due March 22, 2019
Debt Instrument [Line Items]
Short-term Debt		$ 500	$ 498
Senior unsecured floating rate notes due March 22, 2019 \| Senior Notes \| LIBOR
Debt Instrument [Line Items]
Spread on variable rate	0.39%

Debt Obligations (3.875% Senior Unsecured Notes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Jun. 30, 2013
Debt Instrument [Line Items]
Decrease in carrying amount	$ 173
Senior Notes \| 3.875% senior unsecured notes due June 7, 2021
Debt Instrument [Line Items]
Stated rate	3.875%	3.875%
Decrease in carrying amount	$ 30
Senior Notes \| 3.875% senior unsecured notes due June 7, 2021 \| Maximum
Debt Instrument [Line Items]
Maximum interest rate on debt instrument		5.875%

Debt Obligations (4.25% Senior Unsecured Notes) (Details) - Senior Notes - 4.25% senior unsecured notes due June 1, 2024	Dec. 31, 2018	May 31, 2014
Debt Instrument [Line Items]
Stated rate	4.25%	4.25%
Maximum
Debt Instrument [Line Items]
Maximum interest rate on debt instrument		6.25%

Debt Obligations (1.75% Senior Unsecured Notes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	May 31, 2016
Debt Instrument [Line Items]
Decrease in carrying amount	$ 173
Senior Notes \| 1.75% senior unsecured notes due May 19, 2023
Debt Instrument [Line Items]
Stated rate	1.75%	1.75%
Decrease in carrying amount	$ 30
Senior Notes \| 1.75% senior unsecured notes due May 19, 2023 \| Maximum
Debt Instrument [Line Items]
Maximum interest rate on debt instrument		3.75%

Debt Obligations (3.85% Senior Unsecured Notes) (Details) - Senior Notes - 3.85% senior unsecured notes due June 30, 2026	Dec. 31, 2018	Jun. 30, 2016
Debt Instrument [Line Items]
Stated rate	3.85%	3.85%
Maximum
Debt Instrument [Line Items]
Maximum interest rate on debt instrument		5.85%

Debt Obligations (2017 Credit Facility) (Details) - Revolving Credit Facility - $1 billion revolving credit commitment due April 25, 2022 (average interest rate of 2.74% for the period January 1, 2018 through December 31, 2018) - USD ($)	1 Months Ended	12 Months Ended
	Apr. 30, 2017	Dec. 31, 2018
Debt Instrument [Line Items]
Credit facility, borrowing capacity	$ 1,000,000,000	$ 1,000,000,000
Credit facility term	5 years
Line of Credit Facility, Fair Value of Amount Outstanding		0
Unamortized debt issuance expense		4,000,000
Remaining amount available		723,000,000
Option to increase available aggregate amount		500,000,000
Commercial Paper And Letter Of Credit
Debt Instrument [Line Items]
Credit facility, remaining residual borrowing capacity		$ 277,000,000
Minimum
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage		0.125%
Maximum
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage		0.40%

Debt Obligations (2016 Credit Facility) (Details) $ in Millions	Dec. 31, 2018 USD ($)
$400 million senior unsecured term loan facility due November 25, 2019 (average interest rate of 3.48% for the period January 1, 2018 through December 31, 2018)(2)
Debt Instrument [Line Items]
Remaining amount outstanding	$ 100

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References + Details

Retirement Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Employer contribution match, percent match		100.00%
Employer contribution match, percentage of employee contribution		6.00%
Defined contributions plan expense		$ 14	$ 13	$ 11
Cost or expenses included in compensation and benefit expense		22	21	23
Employer contribution amount	$ 22
Plan funded percentage	100.00%
Funded status, underfunded amount		28	60	$ 59
Fair value of plan assets		94	79
Benefit obligation		122	$ 139
Accumulated other comprehensive loss for benefit plan		22
Unrecognized net loss		28
Income tax benefit		$ 6

Retirement Plans (Schedule of Expected Benefit Payments) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2019	$ 6
2020	12
2021	6
2022	7
2023	7
2024 through 2028	40
Total future benefit payments	78
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2019	4
2020	5
2021	4
2022	5
2023	5
2024 through 2028	29
Total future benefit payments	52
SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2019	2
2020	7
2021	2
2022	2
2023	2
2024 through 2028	10
Total future benefit payments	25
Post-retirement
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2019	0
2020	0
2021	0
2022	0
2023	0
2024 through 2028	1
Total future benefit payments	$ 1

Share-Based Compensation (Narrative) (Details) $ / shares in Units, $ in Millions		1 Months Ended	2 Months Ended	3 Months Ended	12 Months Ended
	Jan. 30, 2018	Jan. 31, 2017 $ / shares shares	Feb. 22, 2019 shares	Dec. 31, 2017 $ / shares shares	Dec. 31, 2018 USD ($) program $ / shares peer_group shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares reserved for future issuance (in shares)					11,000,000
Stock option awards granted (in shares)						268,817
Stock options exercised in period (in shares)					118,094	1,102,830	1,219,820
Net cash proceeds from the exercise of stock options \| $					$ 3	$ 24	$ 41
Share price (in dollars per share) \| $ / shares					$ 81.57
Stock options, exercisable (in shares)				300,000	268,504	300,000
Options exercisable, weighted average exercise price (in dollars per share) \| $ / shares				$ 23.55	$ 37.51	$ 23.55
Total pre-tax intrinsic value of stock options exercised \| $					$ 7	$ 54	$ 40
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discount from market price				15.00%	15.00%	15.00%
Common stock shares reserved for future issuance (in shares)					1,900,000
Maximum percentage of shares purchased from annual compensation					10.00%
Discount given to employees					15.00%
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $					$ 55
Weighted-average period unrecognized compensation cost is expected to be recognized, in years					1 year 9 months 1 day
PSUs \| One-Year Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $					$ 14
Weighted-average period unrecognized compensation cost is expected to be recognized, in years					1 year 7 months 1 day
Performance period					1 year
Percentage of target amount granted, minimum					0.00%
Percentage of target amount granted, maximum					150.00%
Vesting period					3 years
PSUs \| Three-Year Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $					$ 28
Weighted-average period unrecognized compensation cost is expected to be recognized, in years					1 year 5 months 2 days
Performance period					3 years
Vesting period					3 years
Number of peer groups \| peer_group					2
Performance-based long-term incentive program weighted percentage					50.00%
Minimum payout					0.00%
Maximum payout					200.00%
Share price (in dollars per share) \| $ / shares				$ 69.45	$ 86.24	$ 69.45
PSUs \| Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance-based programs \| program					2
PSUs, Negative TSR \| Three-Year Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum payout					100.00%
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards granted (in shares)					0
Weighted-average grant date fair value (in dollars per share) \| $ / shares		$ 66.68
Expected life (in years)		6 years
Employee Stock Option \| CEO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Stock option awards granted (in shares)		268,817
Second Anniversary \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Second Anniversary \| Employee Stock Option \| CEO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.33%
Third Anniversary \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					25.00%
Fourth Anniversary \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage					50.00%
Subsequent Event \| PSUs \| One-Year Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional units granted above target (in shares)			51,914
Subsequent Event \| PSUs \| Three-Year Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional units granted above target (in shares)			99,622

Share-Based Compensation (Summary of Share-Based Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based compensation expense before income taxes	$ 69	$ 70	$ 86
Income tax benefit	(19)	(29)	(35)
Share-based compensation expense after income taxes	$ 50	$ 41	$ 51

Share-Based Compensation (Summary of Restricted Stock Activity) (Details) - Restricted stock - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Awards
Unvested balances at beginning of period (in shares)	1,988,500	2,560,578	3,343,738
Granted (in shares)	550,544	737,864	724,200
Vested (in shares)	(702,832)	(1,102,823)	(1,238,980)
Forfeited (in shares)	(252,837)	(207,119)	(268,380)
Unvested balances at end of period (in shares)	1,583,375	1,988,500	2,560,578
Weighted-Average Grant Date Fair Value
Unvested balances at beginning of period (in dollars per share)	$ 57.34	$ 45.92	$ 35.36
Granted (in dollars per share)	81.66	67.48	62.91
Vested (in dollars per share)	48.64	38.56	27.91
Forfeited (in dollars per share)	63.86	52.29	43.29
Unvested balances at end of period (in dollars per share)	$ 68.62	$ 57.34	$ 45.92

Share-Based Compensation (Schedule of Weighted- Average Assumptions Used to Determine Weighted-Average Fair Values) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date share price (in dollars per share)	$ 81.57
PSUs \| Three-Year Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average risk free interest rate	2.36%	1.44%
Expected volatility	18.70%	19.20%
Weighted-average grant date share price (in dollars per share)	$ 86.24	$ 69.45
Weighted-average fair value at grant date (in dollars per share)	$ 116.86	$ 81.57

Share-Based Compensation (Summary of PSU Activity) (Details) - PSUs - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
One-Year Program
Number of Awards
Unvested balances at beginning of period (in shares)	333,004	378,766	423,967
Granted (in shares)	177,831	197,075	242,642
Vested (in shares)	(170,257)	(202,073)	(242,793)
Forfeited (in shares)	(26,347)	(40,764)	(45,050)
Unvested balances at end of period (in shares)	314,231	333,004	378,766
Weighted-Average Grant Date Fair Value
Unvested balances at beginning of period (in dollars per share)	$ 61.39	$ 52.55	$ 41.34
Granted (in dollars per share)	80.97	65.51	58.33
Vested (in dollars per share)	58.49	49.93	39.63
Forfeited (in dollars per share)	61.83	55.92	47.72
Unvested balances at end of period (in dollars per share)	$ 74.01	$ 61.39	$ 52.55
Three-Year Program
Number of Awards
Unvested balances at beginning of period (in shares)	1,009,958	1,314,668	1,439,718
Granted (in shares)	484,075	803,712	761,501
Vested (in shares)	(655,204)	(1,079,925)	(879,926)
Forfeited (in shares)	(1,079)	(28,497)	(6,625)
Unvested balances at end of period (in shares)	837,750	1,009,958	1,314,668
Weighted-Average Grant Date Fair Value
Unvested balances at beginning of period (in dollars per share)	$ 78.18	$ 63.18	$ 49.41
Granted (in dollars per share)	90.92	55.57	66.89
Vested (in dollars per share)	64.08	42.83	43.81
Forfeited (in dollars per share)	81.57	87.86	69.11
Unvested balances at end of period (in dollars per share)	$ 96.57	$ 78.18	$ 63.18

Share-Based Compensation (Summary of Stock Options Valuation Assumptions) (Details) - Employee Stock Option	1 Months Ended
	Jan. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)	6 years
Weighted-average risk free interest rate	2.10%
Expected volatility	25.60%
Dividend yield	$ 0.0192

Share-Based Compensation (Summary of Stock Option Activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of Stock Options
Outstanding at Beginning of period (in shares)	571,380	1,406,371	2,626,487
Granted (in shares)		268,817
Exercised (in shares)	(118,094)	(1,102,830)	(1,219,820)
Forfeited (in shares)	(5,570)	(978)	(296)
Outstanding at End of period (in shares)	447,716	571,380	1,406,371
Stock options, exercisable (in shares)	268,504	300,000
Weighted-Average Exercise Price
Outstanding at Beginning of period (in dollars per share)	$ 43.84	$ 22.32	$ 27.74
Granted (in dollars per share)		66.68
Exercised (in dollars per share)	24.44	21.98	34.00
Forfeited (in dollars per share)	25.29	21.33	23.31
Outstanding at End of period (in dollars per share)	49.19	43.84	$ 22.32
Options exercisable, weighted average exercise price (in dollars per share)	$ 37.51	$ 23.55

Share-Based Compensation (Summary of Stock Option Activity, Outstanding and Exercisable) (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) $ / shares shares
Stock Options
Outstanding, number of stock options (in shares) \| shares	447,716
Outstanding, weighted-average remaining contractual term	5 years 6 months 6 days
Outstanding, weighted-average exercise price (in dollars per share)	$ 49.19
Outstanding, aggregate intrinsic value \| $	$ 15
Exercisable, number of exercisable (in shares) \| shares	268,504
Exercisable, weighted-average remaining contractual term	3 years 10 months 10 days
Exercisable, weighted-average exercise price (in dollars per share)	$ 37.51
Exercisable, aggregate intrinsic value \| $	$ 12
Exercise Price Range One
Stock Options
Outstanding, number of stock options (in shares) \| shares	76,844
Outstanding, weighted-average remaining contractual term	1 year 1 month 30 days
Outstanding, weighted-average exercise price (in dollars per share)	$ 19.74
Outstanding, aggregate intrinsic value \| $	$ 5
Exercisable, number of exercisable (in shares) \| shares	76,844
Exercisable, weighted-average remaining contractual term	1 year 1 month 30 days
Exercisable, weighted-average exercise price (in dollars per share)	$ 19.74
Exercisable, aggregate intrinsic value \| $	$ 5
Exercise Price Range Two
Stock Options
Outstanding, number of stock options (in shares) \| shares	370,872
Outstanding, weighted-average remaining contractual term	6 years 5 months 2 days
Outstanding, weighted-average exercise price (in dollars per share)	$ 55.29
Outstanding, aggregate intrinsic value \| $	$ 10
Exercisable, number of exercisable (in shares) \| shares	191,660
Exercisable, weighted-average remaining contractual term	4 years 11 months 10 days
Exercisable, weighted-average exercise price (in dollars per share)	$ 44.64
Exercisable, aggregate intrinsic value \| $	$ 7
Minimum \| Exercise Price Range One
Stock Options
Range of exercise price, lower range limit (in dollars per share)	$ 18.67
Minimum \| Exercise Price Range Two
Stock Options
Range of exercise price, lower range limit (in dollars per share)	25.28
Maximum \| Exercise Price Range One
Stock Options
Range of exercise price, lower range limit (in dollars per share)	20.1
Maximum \| Exercise Price Range Two
Stock Options
Range of exercise price, lower range limit (in dollars per share)	$ 66.68

Share-Based Compensation (Summary of Employee Stock Purchase Plan) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expenses	$ 69	$ 70	$ 86
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares purchased by employees	205,785	235,859	233,464
Weighted-average price of shares purchased (in dollars per share)	$ 66.79	$ 58.26	$ 50.39
Compensation expenses	$ 3	$ 3	$ 4

Nasdaq Stockholders' Equity (Narrative) (Details)				1 Months Ended		12 Months Ended
Nasdaq Stockholders' Equity (Narrative) (Details)	Jul. 24, 2018 USD ($) $ / shares	Mar. 26, 2018 USD ($) $ / shares	Jan. 30, 2018 USD ($) $ / shares	Jan. 31, 2019 USD ($) $ / shares	Mar. 31, 2018 $ / shares	Dec. 31, 2018 USD ($) vote $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares	Jan. 31, 2018 USD ($)
Stockholders Equity [Line Items]
Common stock, shares authorized (in shares)						300,000,000	300,000,000
Common stock, shares issued (in shares)						170,709,425	172,373,432
Common stock, shares outstanding (in shares)						165,165,104	167,441,030
Common stock (in votes per share) \| vote						1
Common stock holder voting rights, maximum percentage of the then-outstanding shares of Nasdaq common stock						5.00%
Common stock in treasury (in shares)						5,544,321	4,932,402
Share repurchase program additional amount authorized \| $									$ 500,000,000
Share repurchase program, authorized amount \| $									$ 726,000,000
Remaining authorized share repurchase amounts under repurchase program \| $						$ 332,000,000
Number of shares of common stock repurchased (in shares)						4,508,426	2,843,519
Preferred stock, shares authorized (in shares)						30,000,000
Preferred stock par value (in dollars per share) \| $ / shares						$ 0.01
Payments of dividends \| $						$ 280,000,000
Cash dividends declared per common share (in dollars per share) \| $ / shares	$ 0.44	$ 0.44	$ 0.38		$ 0.44	$ 1.7	$ 1.46	$ 1.21
Percent increase over prior quarter dividend						16.00%
Dividends declared \| $	$ 72,000,000	$ 73,000,000	$ 63,000,000			$ 280,000,000	$ 243,000,000	$ 200,000,000
Other Repurchases of Common Stock
Stockholders Equity [Line Items]
Number of shares of common stock repurchased (in shares)						611,919
Series A Preferred Stock
Stockholders Equity [Line Items]
Preferred stock, series A convertible preferred stock, shares issued (in shares)						0	0
Preferred stock, series A convertible preferred stock, shares outstanding (in shares)						0	0
Subsequent Event
Stockholders Equity [Line Items]
Cash dividends declared per common share (in dollars per share) \| $ / shares				$ 0.44
Dividends declared \| $				$ 73,000,000

Nasdaq Stockholders' Equity (Common Stock in Treasury) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity [Abstract]
Number of shares of common stock repurchased (in shares)	4,508,426	2,843,519
Average price paid per share (in dollars per share)	$ 87.43	$ 71.56
Total purchase price	$ 394	$ 203	$ 100

Nasdaq Stockholders' Equity (Schedule of Dividends Declared) (Details) - USD ($) $ / shares in Units, $ in Millions					1 Months Ended	12 Months Ended
	Oct. 24, 2018	Jul. 24, 2018	Mar. 26, 2018	Jan. 30, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Dividends Payable [Line Items]
Dividend per common share (in dollars per share)		$ 0.44	$ 0.44	$ 0.38	$ 0.44	$ 1.7	$ 1.46	$ 1.21
Total Amount		$ 72	$ 73	$ 63		$ 280	$ 243	$ 200
Dividend Declaration Date Fourth Quarter
Dividends Payable [Line Items]
Dividend per common share (in dollars per share)	$ 0.44
Total Amount	$ 72

Earnings Per Share (Summary of Computation of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Numerator:
Net income attributable to common shareholders	$ 458	$ 729	$ 106
Denominator:
Weighted-average common shares outstanding for basic earnings per share (in shares)	165,349,471	166,364,299	165,182,290
Weighted-average effect of dilutive securities:
Employee equity awards (in shares)	1,988,610	2,861,892	3,258,136
Contingent issuance of common stock	353,218	358,840	360,571
Weighted-average common shares outstanding for diluted earnings per share (in shares)	167,691,299	169,585,031	168,800,997
Basic and diluted earnings per share:
Basic earnings per share (in dollars per share)	$ 2.77	$ 4.38	$ 0.64
Diluted earnings per share (in dollars per share)	$ 2.73	$ 4.30	$ 0.63

Fair Value of Financial Instruments (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Assets at Fair Value
Financial investments, at fair value	$ 268	$ 235
Fair Value, Measurements, Recurring
Assets at Fair Value
Financial investments, at fair value	268	235
Default fund and margin deposit investments	1,649	2,129
Total Assets at Fair Value	1,917	2,364
Liabilities at Fair Value
Other financial instruments	112
Total Liabilities at Fair Value	112
Fair Value, Measurements, Recurring \| Level 1
Assets at Fair Value
Financial investments, at fair value	133	135
Default fund and margin deposit investments	327	371
Total Assets at Fair Value	460	506
Liabilities at Fair Value
Other financial instruments	0
Total Liabilities at Fair Value	0
Fair Value, Measurements, Recurring \| Level 2
Assets at Fair Value
Financial investments, at fair value	135	100
Default fund and margin deposit investments	1,322	1,758
Total Assets at Fair Value	1,457	1,858
Liabilities at Fair Value
Other financial instruments	112
Total Liabilities at Fair Value	112
Fair Value, Measurements, Recurring \| Level 3
Assets at Fair Value
Financial investments, at fair value	0	0
Default fund and margin deposit investments	0	0
Total Assets at Fair Value	0	$ 0
Liabilities at Fair Value
Other financial instruments	0
Total Liabilities at Fair Value	$ 0

Fair Value of Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	$ 259	$ 221
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial instruments	112
Fair Value, Measurements, Recurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other financial instruments	112
Fair Value, Measurements, Nonrecurring \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of debt utilizing discounted cash flow analyses	3,900	4,400
Foreign Government Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	$ 166	$ 160

Clearing Operations (Narrative) (Details)	1 Months Ended		12 Months Ended
Clearing Operations (Narrative) (Details)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) fund contract	Dec. 31, 2017 USD ($) contract
Clearing Operations [Line Items]
Number of member sponsored default funds \| fund			4
Loss due to commodities market default		$ 133,000,000
Loss due to commodities market default allocated to junior capital		8,000,000
Increase to commodities market to junior capital		14,000,000
Capital relief program expense	$ 23,000,000
Collateral due to market default	112,000,000		$ 112,000,000
Default funds and margin deposits	4,742,000,000		4,742,000,000	$ 3,988,000,000
Default fund contributions	499,000,000		499,000,000
Committed capital	268,000,000		268,000,000	235,000,000
Liability due to market default	0		0
Liability Waterfall
Clearing Operations [Line Items]
Loss due to commodities market default allocated to junior capital		$ 8,000,000
Junior capital, cash deposits and pledged assets	31,000,000		31,000,000
Senior capital, cash deposits and pledged assets	23,000,000		23,000,000
Committed capital	67,000,000		67,000,000
Utilize as capital resources
Clearing Operations [Line Items]
Default fund contributions	436,000,000		436,000,000
Utilize as member posted surplus balance
Clearing Operations [Line Items]
Default fund contributions	63,000,000		63,000,000
Nasdaq Clearing
Clearing Operations [Line Items]
Default fund cash contributions invested in highly rated government debt securities			$ 1,483,000,000
Maturity period of time deposits			90 days
Committed capital	121,000,000		$ 121,000,000
Power of assessment of the clearing member's contribution to the financial markets and commodities markets default funds			100.00%
Contract value of resale and repurchase agreements	500,000,000		$ 500,000,000	$ 2,300,000,000
Total number of derivative contracts cleared \| contract			9,223,246	8,534,986
Nasdaq Clearing \| Reverse Repurchase Agreements
Clearing Operations [Line Items]
Default funds and margin deposits	$ 166,000,000		$ 166,000,000
Minimum
Clearing Operations [Line Items]
Reverse purchase agreements, maturity range			4 days
Maximum
Clearing Operations [Line Items]
Reverse purchase agreements, maturity range			17 days

Clearing Operations (Schedule of Clearing Member Default Fund Contributions And Margin Deposits) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Clearing Operations [Line Items]
Default fund contributions	$ 499
Margin deposits	7,445
Total	7,944
Cash Contributions
Clearing Operations [Line Items]
Default fund contributions	370
Margin deposits	4,372
Total	4,742
Non-Cash Contributions
Clearing Operations [Line Items]
Default fund contributions	129
Margin deposits	3,073
Total	$ 3,202

Clearing Operations (Schedule of Derivative Contracts) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) TWh shares	Dec. 31, 2017 TWh shares
Clearing Operations [Line Items]
Market value of derivative contracts \| $	$ 2,202
Total number of cleared contracts \| shares	98,506,687	94,152,671
Total volume in cleared power, in Terawatt hours (TWh) \| TWh	1,067	1,199
Commodity and seafood options, futures and forwards
Clearing Operations [Line Items]
Market value of derivative contracts \| $	$ 1,196
Total number of cleared contracts \| shares	1,649,912	2,824,188
Fixed-income options and futures
Clearing Operations [Line Items]
Market value of derivative contracts \| $	$ 600
Total number of cleared contracts \| shares	22,839,794	20,376,383
Stock options and futures
Clearing Operations [Line Items]
Market value of derivative contracts \| $	$ 271
Total number of cleared contracts \| shares	24,978,684	26,023,816
Index options and futures
Clearing Operations [Line Items]
Market value of derivative contracts \| $	$ 135
Total number of cleared contracts \| shares	49,038,297	44,928,284

Leases - (Future Minimum Lease Payments) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Gross Lease Commitments
Operating Leased Assets [Line Items]
2019	$ 80
2020	74
2021	66
2022	48
2023	45
Thereafter	347
Total future minimum lease payments	660
Sublease Income
Operating Leased Assets [Line Items]
2019	5
2020	5
2021	4
2022	4
2023	3
Thereafter	2
Total future minimum lease payments	23
Net Lease Commitments
Operating Leased Assets [Line Items]
2019	75
2020	69
2021	62
2022	44
2023	42
Thereafter	345
Total future minimum lease payments	$ 637

Income Taxes (Domestic and Foreign Components of Income Before Income Tax Provision) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Domestic	$ 636	$ 556	$ (153)
Foreign	428	316	286
Income before income taxes	$ 1,064	$ 872	$ 133

Income Taxes (Components of Income Tax Provision) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current income tax provision:
Federal	$ 103	$ 51	$ 37
State	56	17	21
Foreign	146	68	106
Total current income taxes	305	136	164
Deferred income tax provision (benefit):
Federal	185	(16)	(98)
State	116	24	(35)
Foreign	0	(1)	(4)
Total deferred income provision (benefit)	301	7	(137)
Total income tax provision	$ 606	$ 143	$ 27

Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Mar. 31, 2018
Income Tax Disclosure [Line Items]
Undistributed earnings		$ 387
Income tax benefits primarily related to share-based compensation		9	$ 40	$ 41
Unrecognized tax benefits that would impact effective tax rate	$ 45	43	45	48
decrease in unrecognized tax benefits, reasonably possible		12
Penalties and interest expense		2	1	$ 2
Interest and penalties related to income tax	9	10	9
Payments for tax settlements		40
Provisional tax benefit, due to Tax Cuts and Jobs Act	$ 89		$ (89)
Reduction to deferred tax assets relating to foreign currency translation		(290)
Foreign Tax Authority \| Sweden
Income Tax Disclosure [Line Items]
Tax expense (benefits) associated with foreign tax agency					$ 41	$ (56)
Tax expense (benefits), per diluted share (in dollars per share)					$ 0.24
Quarterly recurring tax expense		1
Accumulated Other Comprehensive Loss \| Accounting Standards Update 2018-02
Income Tax Disclosure [Line Items]
Reclassification from AOCI, tax amount		(417)
Retained Earnings \| Accounting Standards Update 2018-02
Income Tax Disclosure [Line Items]
Reclassification from AOCI, tax amount		$ 417

Income Taxes (Reconciliation of Provision of Income Taxes) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal income tax provision at the statutory rate	21.00%	35.00%	35.00%
State income tax provision, net of federal effect	3.70%	2.60%	(6.70%)
Change in deferred taxes due to change in law	27.00%	(9.90%)	(1.20%)
Excess tax benefits related to employee share-based compensation	(0.70%)	(4.00%)	0.00%
Non-U.S. subsidiary earnings	0.10%	(6.00%)	(7.30%)
Tax credits and deductions	(0.20%)	(1.00%)	(5.10%)
Change in unrecognized tax benefits	4.70%	(0.80%)	4.20%
Other, net	1.40%	0.50%	1.40%
Actual income tax provision	57.00%	16.40%	20.30%

Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Deferred revenues	$ 19	$ 25
U.S. federal net operating loss	0	1
Foreign net operating loss	23	30
State net operating loss	4	4
Compensation and benefits	33	42
Foreign currency translation	0	292
Tax credits	0	7
Federal benefit of uncertain tax positions	17	0
Other	25	20
Gross deferred tax assets	121	421
Less: valuation allowance	(23)	(30)
Total deferred tax assets, net of valuation allowance	98	391
Deferred tax liabilities:
Amortization of software development costs and depreciation	(41)	(47)
Amortization of acquired intangible assets	(498)	(510)
Investments	(34)	(26)
Other	(22)	(19)
Gross deferred tax liabilities	(595)	(602)
Net deferred tax liabilities	(497)	(211)
Non-current deferred tax assets	4	14
Deferred tax liabilities, net	$ (501)	$ (225)

Income Taxes (Net Operating Losses and Credits) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards, subject to expiration	$ 3
Net operating loss carryforwards, not subject to expiration	20
State and local jurisdiction
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards, subject to expiration	$ 4

Income Taxes (Reconciliation of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 45	$ 48	$ 40
Additions as a result of tax positions taken in prior periods	28	2	9
Additions as a result of tax positions taken in the current period	6	5	3
Reductions related to settlements with taxing authorities	(23)	0	(4)
Reductions as a result of lapses of the applicable statute of limitations	(4)	(10)	0
Ending balance	$ 52	$ 45	$ 48

Restructuring Charges (Summary of Restructuring Charges) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$ 0	$ 0	$ 41
Severance and other termination benefits
Restructuring Cost and Reserve [Line Items]
Total restructuring charges			22
Facilities-related
Restructuring Cost and Reserve [Line Items]
Total restructuring charges			1
Asset impairments
Restructuring Cost and Reserve [Line Items]
Total restructuring charges			8
Other
Restructuring Cost and Reserve [Line Items]
Total restructuring charges			$ 10

Restructuring Charges (Narrative) (Details) $ in Millions	12 Months Ended
Restructuring Charges (Narrative) (Details) $ in Millions	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) employee
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ 0	$ 41
Severance and other termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 22
Number of positions eliminated \| employee			201
Restructuring reserve			$ 17
Asset impairments
Restructuring Cost and Reserve [Line Items]
Restructuring charges			8
Other
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 10

Commitments, Contingencies and Guarantees (Details)		12 Months Ended
Commitments, Contingencies and Guarantees (Details)	Sep. 02, 2014 exchange	Dec. 31, 2018 USD ($) shares	Oct. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Commitments and Contingencies Disclosure [Line Items]
Financial guarantees obtained		$ 12,000,000		$ 14,000,000
National exchanges named as defendants \| exchange	7
Estimate of possible legal fees			$ 1,000,000
eSpeed
Commitments and Contingencies Disclosure [Line Items]
Contingent future issuance of common stock (in shares) \| shares		992,247
Revenue required to trigger annual issuance of Nasdaq common stock		$ 25,000,000
Escrow Agreement
Commitments and Contingencies Disclosure [Line Items]
Contingency, accrual		12,000,000
Clearinghouse Credit Facilities
Commitments and Contingencies Disclosure [Line Items]
Credit facility, available liquidity		220,000,000		$ 187,000,000
ICBC
Commitments and Contingencies Disclosure [Line Items]
Margin deposits contributed to brokers		15,000,000
Contribution of Equity Capital \| OCC
Commitments and Contingencies Disclosure [Line Items]
Commitment contributions		$ 200,000,000
OCC
Commitments and Contingencies Disclosure [Line Items]
Ownership percentage		40.00%
OCC \| Contribution of Equity Capital
Commitments and Contingencies Disclosure [Line Items]
Commitment contributions		$ 80,000,000

Business Segments (Narrative) (Details) $ in Millions	1 Months Ended		12 Months Ended
Business Segments (Narrative) (Details) $ in Millions	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment			4
Segment Reporting Information [Line Items]
Expenses related to clearing default			$ 31
Loss due to commodities market default allocated to junior capital		$ 8
Increase decrease in total assets			346	$ 2,000
Capital relief program expense	$ 23
Restructuring charges			$ 0	$ 0	$ 41
Liability Waterfall
Segment Reporting Information [Line Items]
Loss due to commodities market default allocated to junior capital		$ 8

Business Segments (Schedule of Operating Segments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total revenues	$ 4,277	$ 3,948	$ 3,704
Transaction-based expenses	(1,751)	(1,537)	(1,428)
Revenues less transaction-based expenses	2,526	2,411	2,276
Depreciation and amortization	210	188	170
Operating income (loss)	1,028	991	836
Total assets	15,700	15,354	13,411
Purchase of property and equipment	111	144	134
Operating Segments \| Market Services
Segment Reporting Information [Line Items]
Total revenues	2,709	2,418	2,255
Transaction-based expenses	(1,751)	(1,537)	(1,428)
Revenues less transaction-based expenses	958	881	827
Depreciation and amortization	95	95	87
Operating income (loss)	544	481	450
Total assets	10,299	9,471	8,626
Purchase of property and equipment	28	59	62
Operating Segments \| Corporate Services
Segment Reporting Information [Line Items]
Total revenues	528	501	477
Transaction-based expenses	0	0	0
Revenues less transaction-based expenses	528	501	477
Depreciation and amortization	41	44	42
Operating income (loss)	163	158	130
Total assets	734	865	1,263
Purchase of property and equipment	29	41	37
Operating Segments \| Information Services
Segment Reporting Information [Line Items]
Total revenues	714	588	540
Transaction-based expenses	0	0	0
Revenues less transaction-based expenses	714	588	540
Depreciation and amortization	51	26	18
Operating income (loss)	460	418	383
Total assets	3,352	3,420	2,439
Purchase of property and equipment	17	10	8
Operating Segments \| Market Technology
Segment Reporting Information [Line Items]
Total revenues	270	247	241
Transaction-based expenses	0	0	0
Revenues less transaction-based expenses	270	247	241
Depreciation and amortization	21	14	13
Operating income (loss)	34	57	73
Total assets	467	572	497
Purchase of property and equipment	37	34	27
Corporate Items
Segment Reporting Information [Line Items]
Total revenues	56	194	191
Transaction-based expenses	0	0	0
Revenues less transaction-based expenses	56	194	191
Depreciation and amortization	2	9	10
Operating income (loss)	(173)	(123)	(200)
Total assets	848	1,026	586
Purchase of property and equipment	$ 0	$ 0	$ 0

Business Segments (Corporate Items) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues - divested businesses		$ 4,277	$ 3,948	$ 3,704
Expenses:
Amortization expense of acquired intangible assets		109	92	82
Merger and strategic initiatives expense		21	44	76
Clearing default	$ 8
Extinguishment of debt		0	(9)	0
Restructuring charges		0	0	41
Regulatory matter		32	33	35
Expenses - divested businesses		1,498	1,420	1,440
Executive compensation		712	670	665
Operating income		1,028	991	836
Corporate Items
Segment Reporting Information [Line Items]
Revenues - divested businesses		56	194	191
Expenses:
Amortization expense of acquired intangible assets		109	92	82
Merger and strategic initiatives expense		21	44	76
Clearing default		31	0	0
Extinguishment of debt		0	10	0
Restructuring charges		0	0	41
Regulatory matter		0	0	6
Expenses - divested businesses		51	167	168
Executive compensation		0	0	12
Other		17	4	6
Total expenses		229	317	391
Operating income		$ (173)	$ (123)	$ (200)

Business Segments (Geographic Data) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 4,277	$ 3,948	$ 3,704
Property and equipment, net	376	400	362
United States
Segment Reporting Information [Line Items]
Revenues	3,379	3,081	2,679
Property and equipment, net	224	247	244
All other countries
Segment Reporting Information [Line Items]
Revenues	898	867	1,025
Property and equipment, net	$ 152	$ 153	$ 118

Subsequent Events (Details) - OSLO BORS ASA - Scenario, Forecast $ / shares in Units, kr in Millions, $ in Millions	1 Months Ended
	Mar. 04, 2019 USD ($)	Mar. 04, 2019 NOK (kr)	Jan. 29, 2019 $ / shares
Subsequent Event [Line Items]
NOK per share offering (in NOK per share)			$ 152
Interest rate on offer price	6.00%	6.00%
Purchase Consideration	$ 770	kr 6,537
Required percentage of votes for approval, minimum	90.00%	90.00%

Debt Obligations (Senior Unsecured Notes) (Details)	12 Months Ended
Debt Obligations (Senior Unsecured Notes) (Details)	Dec. 31, 2018
Senior Notes \| Senior Notes Excluding 2020 Notes
Debt Instrument [Line Items]
Aggregate principal amount purchased plus accrued and unpaid interest	101.00%

Summary of Significant Accounting Policies - Summary of Recent Accounting Pronouncements (Details) - Accounting Standards Update 2018-02 $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Accumulated Other Comprehensive Loss
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI, tax amount	$ (417)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI, tax amount	$ 417

Debt Obligations (Other Credit Facilities) (Details) - Clearinghouse Credit Facilities - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Letter of Credit
Debt Instrument [Line Items]
Remaining amount available	$ 220
Commercial Paper And Letter Of Credit
Debt Instrument [Line Items]
Remaining amount available		$ 187

Earnings Per Share (Narrative) (Details) - shares	12 Months Ended
Earnings Per Share (Narrative) (Details) - shares	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Antidilutive securities	0	267,465	264,134

Leases - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Leases - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Leases [Abstract]
Operating sublease income	$ 5	$ 3	$ 4
Rent expense for operating leases	$ 82	$ 83	$ 78