Nasdaq (NDAQ) 10-Q 6 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	Apr. 28, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	ndaq
Entity Registrant Name	NASDAQ OMX GROUP, INC.
Entity Central Index Key	1120193
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		168,618,071

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Millions, unless otherwise specified
Current assets:
Cash and cash equivalents	$328		$427
Restricted cash	19		49
Financial investments, at fair value	194	[1]	174	[1]
Receivables, net	344		389
Deferred tax assets	23		16
Default funds and margin deposits	2,635		2,194
Other current assets	145		151
Total current assets	3,688		3,400
Property and equipment, net	281		292
Non-current deferred tax assets	652		536
Goodwill	5,350		5,538
Intangible assets, net	1,995		2,077
Other non-current assets	276		244
Total assets	12,242		12,087
Current liabilities:
Accounts payable and accrued expenses	207		189
Section 31 fees payable to SEC	82		124
Accrued personnel costs	71		143
Deferred revenue	282		177
Other current liabilities	133		116
Deferred tax liabilities	30		37
Default funds and margin deposits	2,635		2,194
Total current liabilities	3,440		2,980
Debt obligations	2,306	[2]	2,313	[2]
Non-current deferred tax liabilities	587		626
Non-current deferred revenue	210		215
Other non-current liabilities	154		159
Total liabilities	6,697		6,293
Commitments and contingencies
Nasdaq stockholders' equity:
Common stock, $0.01 par value, 300,000,000 shares authorized, shares issued: 171,527,299 at March 31, 2015 and 170,325,304 at December 31, 2014; shares outstanding: 168,972,790 at March 31, 2015 and 168,795,263 at December 31, 2014	2		2
Additional paid-in capital	3,243		3,222
Common stock in treasury, at cost: 2,599,509 shares at March 31, 2015 and 1,530,041 shares at December 31, 2014	-94		-41
Accumulated other comprehensive loss	-883		-682
Retained earnings	3,276		3,292
Total Nasdaq stockholders' equity	5,544		5,793
Noncontrolling interests	1		1
Total equity	5,545		5,794
Total liabilities and equity	$12,242		$12,087
[1]	As of March 31, 2015 and December 31, 2014, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. Of these securities, $164 million as of March 31, 2015 and $159 million as of December 31, 2014 are assets utilized to meet regulatory capital requirements, primarily for the clearing operations of Nasdaq Nordic Clearing. As of March 31, 2015 and December 31, 2014, Level 2 financial investments, at fair value were primarily comprised of available-for-sale investment securities in short-term commercial paper.
[2]	See “2014 Credit Facility” below for further discussion.

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Condensed Consolidated Balance Sheets [Abstract]
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	171,527,299	170,325,304
Common stock, shares outstanding	168,927,790	168,795,263
Common stock in treasury	2,599,509	1,530,041

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Income (USD $)	3 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues:
Market Services	$539	$577
Listing Services	64	58
Information Services	125	123
Technology Solutions	130	140
Total revenues	858	898
Transaction-based expenses:
Transaction rebates	-261	-285
Brokerage, clearance and exchange fees	-90	-84
Revenues less transaction-based expenses	507	529
Operating expenses:
Compensation and benefits	147	158
Marketing and advertising	7	8
Depreciation and amortization	34	35
Professional and contract services	33	39
Computer operations and data communications	35	22
Occupancy	21	25
Regulatory	7	7
Merger and strategic initiatives		28
General, administrative and other	46	23
Restructuring Charges	150	0
Total operating expenses	480	345
Operating income	27	184
Interest income	1	2
Interest expense	-28	-30
Net income from unconsolidated investees	14
Income before income taxes	14	156
Income tax provision	5	53
Net income attributable to Nasdaq	$9	$103
Per share information:
Basic earnings per share	$0.05	$0.61
Diluted earnings per share	$0.05	$0.59
Cash dividends declared per common share	$0.15	$0.28

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (Loss) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Condensed Consolidated Statements of Comprehensive Income (Loss) [Abstract]
Net income	$9	$103
Foreign currency translation gains (losses):
Net foreign currency translation losses	-314	-12
Income tax benefit	113	8
Total other comprehensive income loss, net of tax	-201	-4
Comprehensive income (loss) attributable to Nasdaq	($192)	$99

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$9	$103
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	34	35
Share-based compensation	14	14
Excess tax benefits related to share-based payments	-2	-3
Deferred income taxes	-55	-10
Non-cash restructuring charges	128
Non-cash merger and strategic initiatives		18
Net income from unconsolidated investees	-14
Other reconciling items included in net income	3	4
Net change in operating assets and liabilities, net of effects of acquisition:
Receivables, net	36	-42
Other assets	17	-17
Accounts payable and accrued expenses	36	-1
Section 31 fees payable to SEC	-42	-8
Accrued personnel costs	-67	-58
Deferred revenue	121	128
Other liabilities	13	20
Net cash provided by operating activities	231	183
Cash flows from investing activities:
Purchases of trading securities	-60	-96
Proceeds from sales and redemptions of trading securities	29	93
Purchases of available-for-sale investment securities	-12	-5
Proceeds from sale of available-for-sale investment securities	3
Capital contribution in equity method investment	-30
Acquisition of businesses, net of cash and cash equivalents acquired	-226
Purchases of property and equipment	-24	-31
Other investment activities	-6	-7
Net cash used in investing activities	-326	-46
Cash flows from financing activities:
Payments of debt obligations	-25	-146
Proceeds from utilization of credit commitment	100	25
Cash paid for repurchase of common stock	-30
Cash dividends	-25	-22
Proceeds received from employee stock activity	6	7
Payments related to employee shares withheld for taxes	-24	-21
Excess tax benefits related to share-based payments	2	3
Other financing activities		1
Net cash provided by (used in) financing activities	4	-153
Effect of exchange rate changes on cash and cash equivalents	-8	2
Net decrease in cash and cash equivalents	-99	-14
Cash and cash equivalents at beginning of period	427	398
Cash and cash equivalents at end of period	328	384
Cash paid for:
Interest	27	36
Income taxes, net of refund	18	11
Non-cash investing activities:
Cost method investments		$75

Organization_and_Nature_of_Ope

Organization and Nature of Operations	3 Months Ended
	Mar. 31, 2015
Organization and Nature of Operations [Abstract]
Organization and Nature of Operations	1. Organization and Nature of Operations
	We are a leading provider of trading, clearing, exchange technology, regulatory, securities listing, information and public company services across six continents. Our global offerings are diverse and include trading and clearing across multiple asset classes, access services, data products, financial indexes, capital formation solutions, corporate solutions and market technology products and services. Our technology powers markets across the globe, supporting equity derivatives trading, clearing and settlement, cash equity trading, fixed income trading and many other functions.
	We manage, operate and provide our products and services in four business segments: Market Services, Listing Services, Information Services and Technology Solutions.
	Market Services
	Our Market Services segment includes our equity derivative trading and clearing, cash equity trading, fixed income, currency and commodities trading and clearing, or FICC, and access and broker services businesses. We operate multiple exchanges and other marketplace facilities across several asset classes, including derivatives, commodities, cash equity, debt, structured products and ETFs. 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 three options exchanges, as well as three cash equity exchanges. The NASDAQ Stock Market, the largest of our cash equities exchanges, is the largest single pool of liquidity for trading U.S.-listed cash equities. We also operate a leading electronic platform for trading of U.S. Treasuries.
	In Europe, we operate exchanges in Stockholm (Sweden), Copenhagen (Denmark), Helsinki (Finland), and Iceland, as well as the clearing operations of Nasdaq Nordic Clearing. 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 and depository receipts, warrants, convertibles, rights, fund units and ETFs, as well as trading and clearing of derivatives and clearing of resale and repurchase agreements. Through Nasdaq First North, our Nordic and Baltic operations also offer alternative marketplaces for smaller companies.
	In addition, Nasdaq Commodities operates a power derivatives exchange regulated in Norway and a European carbon exchange. In the U.K., we operate Nasdaq NLX, a London-based multilateral trading venue that offers a range of both short-term interest rate and long-term interest rate euro- and sterling-based listed derivative products.
	Through our access 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, DROP functionality and connectivity to various data feeds. We also provide co-location services to market participants, whereby firms may lease cabinet space and power to house their own equipment and servers within our data center. Our broker services operations offer technology and customized securities administration solutions to financial participants in the Nordic market.
	Listing Services
	Our Listing Services segment 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. We also operate The NASDAQ Private Market, LLC, or NPM, a marketplace for private growth companies.
	As of March 31, 2015, The NASDAQ Stock Market was home to 2,779 listed companies with a combined market capitalization of approximately $8.2 trillion, and in Europe, the Nasdaq Nordic and Nasdaq Baltic exchanges, together with Nasdaq First North, were home to 804 listed companies with a combined market capitalization of approximately $1.3 trillion.
	Information Services
	Our Information Services segment includes our Data Products and our Index Licensing and Services businesses.
	Our Data Products business sells and distributes historical and real-time quote and trade information to market participants and data distributors. Our data products enhance transparency of the market activity within the exchanges that we operate and provide critical information to financial professional and individual investors globally.
	Our Index Licensing and Services business develops and licenses Nasdaq branded indexes, associated derivatives, and financial products and also provides custom calculation services for third-party clients. We currently calculate and distribute over 42,000 indexes. We had over $105 billion of assets under management in exchange traded products tracking Nasdaq indexes as of March 31, 2015.
	Technology Solutions
	Our Technology Solutions segment includes our Corporate Solutions and Market Technology businesses.
	Our Corporate Solutions business serves corporate clients, including companies listed on our exchanges. We help organizations manage the two-way flow of information with their key constituents, including their board members and investors, and with clients and the public through our suite of advanced technology, analytics, and consultative services. Our Corporate Solutions business primarily offers products to serve the following key areas: investor relations, public relations, multimedia solutions, and governance. We currently have approximately 10,000 Corporate Solutions clients.
	Our Market Technology business is a leading global technology solutions provider and partner to exchanges, clearing organizations, central securities depositories, regulators, banks, brokers 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, energy products and derivatives, and are currently powering more than 70 marketplaces in 50 countries. Market Technology also provides market surveillance services to broker-dealer firms worldwide, as well as enterprise governance, risk management and compliance software solutions.

Basis_of_Presentation_and_Prin

Basis of Presentation and Principles of Consolidation	3 Months Ended
	Mar. 31, 2015
Basis of Presentation and Principles of Consolidation [Abstract]
Basis of Presentation and Principles of Consolidation	2. Basis of Presentation and Principles of Consolidation
	The condensed consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP. The condensed consolidated financial statements 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. As permitted under U.S. GAAP, for certain equity method investments for which financial information is not sufficiently timely for us to apply the equity method of accounting currently, we record our share of the earnings or losses of the investee from the most recently available financial statements on a lag. See “Equity Method Investments,” of Note 6, “Investments,” for further discussion of our equity method investments.
	The accompanying condensed consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. These adjustments are of a normal recurring nature. All significant intercompany accounts and transactions have been eliminated in consolidation.
	As permitted under U.S. GAAP, certain footnotes or other financial information can be condensed or omitted in the interim condensed consolidated financial statements. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in Nasdaq’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014.
	Certain prior period amounts have been reclassified to conform to the current period presentation.
	The preparation of condensed 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 condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
	We have evaluated subsequent events through the issuance date of this Quarterly Report on Form 10-Q. See Note 17, “Subsequent Events,” for further discussion.
	Income Tax Matters
	We use the asset and liability method to determine income taxes on all transactions recorded in the condensed consolidated financial statements. 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 condensed consolidated financial statements. Interest and/or penalties related to income tax matters are recognized in income tax expense.
	Nasdaq’s income tax provision was $5 million in the first quarter of 2015 compared with $53 million in the first quarter of 2014. The overall effective tax rate was 36% in the first quarter of 2015 and 34% in the first quarter of 2014. The higher effective tax rate in the first quarter of 2015 when compared with the same period in 2014 is primarily due to adjustments related to prior year tax liabilities which resulted in an increase to the tax provision. 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 history of pre-tax earnings and losses, are taken into account in assessing the ability to realize deferred tax assets.
	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 2011 and 2012 are currently under audit by the Internal Revenue Service and we are subject to examination for years 2008 through 2010 and 2013. Several state tax returns are currently under examination by the respective tax authorities for the years 2005 through 2013. Non-U.S. tax returns are subject to examination by the respective tax authorities for the years 2008 through 2013. We anticipate that the amount of unrecognized tax benefits at March 31, 2015 will significantly decrease in the next twelve months as we expect to settle certain tax audits. The final outcome of such audits cannot yet be determined. We anticipate that such adjustments will not have a material impact on our consolidated financial position or results of operations.
	In the fourth quarter of 2010, we received an appeal from the Finnish Tax Authority challenging certain interest expense deductions claimed by Nasdaq in Finland for the year 2008. The appeal also demanded certain penalties be paid with regard to the company’s tax return filing position. In October 2012, the Finnish Appeals Board disagreed with the company’s tax return filing position for years 2009 through 2011, even though the tax return position with respect to this deduction was previously reviewed and approved by the Finnish Tax Authority. In June 2014, the Finnish Administrative Court also disagreed with the company’s tax return filing position for these years. We have appealed this ruling to the Finnish Supreme Administrative Court and expect to receive a favorable decision. Through March 31, 2015, we have recorded tax benefits of $24 million associated with this filing position. We have paid $35 million to the Finnish tax authorities, which includes $11 million in interest and penalties. We expect the Finnish Supreme Administrative Court to agree with our position, which would result in an expected refund to Nasdaq of $30 million, which reflects the impact of foreign currency translation. If the Finnish Supreme Administrative Court disagrees with our position, we would record tax expense of $30 million, or $0.17 per diluted share.
	From 2009 through 2012, we recorded tax benefits associated with certain interest expense incurred in Sweden. Our position is supported by a 2011 ruling we received from the Swedish Supreme Administrative Court. However, under new legislation effective January 1, 2013, limitations are imposed on certain forms of interest expense. Because this legislation is unclear with regard to our ability to continue to claim such interest deductions, Nasdaq filed an application for an advance tax ruling with the Swedish Tax Council for Advance Tax Rulings. In June 2014, we received an unfavorable ruling from the Swedish Tax Council for Advance Tax Rulings. We appealed this ruling to the Swedish Supreme Administrative Court; however the Swedish Supreme Administrative Court has denied our request for a ruling based on procedural requirements. As a result of the Swedish Supreme Administrative Court’s denial to provide a ruling, we will appeal to the Lower Administrative Court. We continue to expect a favorable decision. Since January 1, 2013, we have recorded tax benefits of $35 million, or $0.20 per diluted share, related to this matter. We expect to record recurring quarterly tax benefits of $3 million to $4 million with respect to this issue for the foreseeable future.
	Other Tax Matter
	In December 2012, the Swedish Tax Agency approved our 2010 amended value added tax, or VAT, tax return and we received a cash refund for the amount claimed. In 2013, we filed amended VAT tax returns for 2011 and 2012, utilizing the same approach which was approved for the 2010 filing. We also utilized this approach in our 2013 and 2014 filings. However, even though the VAT return position was previously reviewed and approved by the Swedish Tax Agency, the Swedish Tax Agency challenged our approach. The revised position of the Swedish Tax Agency was upheld by the Lower Administrative Court during the first quarter of 2015. As a result, in the first quarter of 2015, we reversed the previously recorded benefit of $12 million, based on the court decision. We will appeal the ruling of the Lower Administrative Court to the Court of Appeals.
	Recently Announced Accounting Pronouncements
	In April 2015, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, 2015-03, “Simplifying the Presentation of Debt Issuance Costs,” which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the debt liability rather than as an asset. The recognition and measurement guidance for debt issuance costs is not affected by this new guidance. Debt issuance costs will continue to be amortized as interest expense using the effective interest method. This guidance will be effective for us on January 1, 2016. Early adoption is permitted. The adoption of this guidance will not have a material impact on our consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (Topic 606),” which supersedes the revenue recognition guidance in Accounting Standards Codification, or ASC, 605, “Revenue Recognition.” The new revenue recognition standard sets forth a five-step revenue recognition model to determine when and how revenue is recognized. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration it expects to receive in exchange for those goods or services. The standard also requires more detailed disclosures. The standard provides alternative methods of initial adoption and will be effective for us on January 1, 2017. Early adoption is not permitted. We are currently assessing the impact that this standard will have on our consolidated financial statements.

Restructuring_Charges

Restructuring Charges	3 Months Ended
	Mar. 31, 2015
Restructuring Charges [Abstract]
Restructuring Charges	3. Restructuring Charges
	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. In the first quarter of 2015, we also decided to change our company name from The NASDAQ OMX Group, Inc. to Nasdaq, Inc., pending regulatory approval. We currently estimate that we will recognize pre-tax restructuring charges of $182 million, consisting of the rebranding of our trade name, severance, asset impairments, facility-related and other costs. During the three months ended March 31, 2015, we recognized restructuring charges of $150 million, with the remaining amount to be recognized through June 2016. Through this initiative, we expect to generate pre-tax savings in 2015 of approximately $17 million and annualized savings of $19 million. Restructuring charges are recorded on restructuring plans that have been committed to by management and are, in part, based upon management's best estimates of future events. Changes to the estimates may require future adjustments to the restructuring liabilities. There were no restructuring charges in the comparable period of 2014.
	The following table presents a summary of restructuring charges in the Condensed Consolidated Statements of Income:
		Three Months Ended March 31, 2015
		(in millions)
	Rebranding of trade name	$	119
	Severance		18
	Facilities-related		3
	Asset impairments		9
	Other		1
	Total restructuring charges	$	150
	Rebranding of Trade Name
	As noted above, in connection with our global rebranding initiative, we decided to change our company name from The NASDAQ OMX Group, Inc. to Nasdaq, Inc., pending regulatory approval. In connection with this action, we decided to discontinue the use of the OMX trade name and recorded a pre-tax, non-cash impairment charge of $119 million because we no longer attribute any material value to the trade name. The impairment charge did not impact the company's consolidated cash flows, liquidity, or capital resources.
	Severance
	Severance, other termination benefits and other associated costs of $18 million related to workforce reductions of 199 positions across our organization. In addition to reducing our workforce, we have relocated certain functions to lower cost locations and will continue hiring in these lower cost locations to support the business.
	Facilities-related
	Facility-related costs of $3 million pertained to the consolidation of leased facilities during the first quarter of 2015.
	Asset Impairments
	Asset impairment charges of $9 million primarily related to fixed assets and capitalized software that were retired during the first quarter of 2015.
	Restructuring Reserve
	The following table presents the changes in the restructuring reserve during the three months ended March 31, 2015:
		Balance at        January 1, 2015			Expense Incurred		Cash     Payments	Balance at         March 31, 2015
		(in millions)
	Severance	$	-	$	18	$	-1	$	17
	Facilities-related		-		3		-2		1
	Total	$	-	$	21	$	-3	$	18
	As of March 31, 2015, the majority of the restructuring reserve is included in other current liabilities in the Condensed Consolidated Balance Sheets and will be paid during the remainder of 2015.

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2015
Acquisitions [Abstract]
Acquisitions and Divestitures	4. Acquisition
	We completed the following acquisition in 2015. Financial results are included in our Condensed Consolidated Statements of Income from the date of the acquisition.
			Purchase Consideration			Total Net Assets (Liabilities) Acquired		Purchased Intangible Assets		Goodwill
			(in millions)
	Dorsey, Wright & Associates, LLC		$	226		$	-26	$	141	$	111
	Acquisition of Dorsey, Wright & Associates, LLC
	On January 30, 2015, we completed the acquisition of Dorsey, Wright & Associates, LLC, or DWA, for $226 million  ($225 million cash paid plus $1 million in working capital adjustments). DWA is a market leader in data analytics, passive indexing and smart beta strategies. We acquired net assets, at fair value, totaling $8 million and recorded a current deferred tax liability of $1 million and a non-current deferred tax liability of $33 million related to differences in the U.S. GAAP and tax basis of our investment in DWA, resulting in total net liabilities acquired of $26 million. DWA is part of our Information Services segment.
	Nasdaq used cash on hand and borrowed $100 million under the revolving credit commitment of our current credit facility to fund this acquisition.
	Intangible Assets
	The following table presents the details of the purchased intangible assets acquired in the acquisition of DWA. All purchased intangible assets with finite lives are amortized using the straight-line method.
					Estimated
					Average Remaining
		Value			Useful Life
	Intangible assets:		(in millions)		(in years)
	Trade name	$	108		Indefinite
	Customer relationships		29		15 years
	Technology		4		5 years
	Total intangible assets	$	141
	Trade Name
	The DWA trade name is recognized in the industry and carries a reputation for quality. As such, DWA’s reputation and positive recognition embodied in the trade name is a valuable asset to Nasdaq. The trade name was considered the primary asset acquired in this transaction. In valuing the acquired trade name, we used the income approach, specifically the 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.
	A discount rate of 17% was utilized, which reflects the amount of risk associated with the hypothetical cash flows generated by the DWA trade name in the future. In developing a discount rate for the trade name, 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 a rate of 36.5%, and a discounted tax amortization benefit was added to the fair value of the asset under the assumption that the trade name would be amortized for tax purposes over a period of 15 years.
	We estimated the useful life of the trade name to be indefinite. The useful life was based on several factors including the number of years the name has been in service, its popularity within the industry, and our intention to continue its use in the branding of products.
	Customer Relationships
	Customer relationships represent the non-contractual and contractual relationships that DWA has with its customers. The DWA customer relationships were valued individually for each of DWA’s businesses using the income approach, specifically the with-and-without method. The with-and-without method is commonly used when the cash flows of a business can be estimated with and without the asset in place. The premise associated with this valuation technique is that the value of an asset is represented by the differences in the subject business’ cash flows under scenarios where (a) the asset is present and is used in operations (with); and (b) the asset is absent and not used in operations (without). Cash flow differentials are then discounted to present value to arrive at an estimate of fair value for the asset.
	We estimated that without current customer relationships, it would take approximately 3-6 years, depending on the business, for the customer base to grow to 100% of current projected revenues. We also made estimates related to compensation levels and other expenses such as sales and marketing that would be incurred as the business was ramped up through the year in which the customer base would be expected to reach the level that currently exists.
	A discount rate of 17.5%, which reflects the estimated weighted average cost of capital for the overall business plus a premium of 0.5% reflecting the risk and uncertainty of the cash flows for the customer relationships relative to the overall business, was utilized when discounting the cash flows. The resulting discounted cash flows were then tax-effected at a rate of 36.5%, and a discounted tax amortization benefit was added to the fair value of the asset under the assumption that the customer relationships would be amortized for tax purposes over a period of 15 years.
	Based on the historical behavior of the customers and a parallel analysis of the customers using the excess earnings method, we estimated the remaining useful life for the acquired customer relationships to be 15 years.
	Technology
	The fair value of the DWA acquired developed technology was 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 intangible asset and discounted to present value.
	To determine the royalty rate we searched for and identified market transactions and royalty rates for comparable technology. In addition, we performed a profit split analysis that produced a range of royalty rates that were then compared for reasonableness to the royalty rates identified in the market transactions and royalty rates for comparable technology. Profit split theory states that a reasonable market participant would be willing and able to make revenue-based royalty payments of 25 to 30 percent of their operating profit to receive the rights to certain licensable intellectual property necessary for conducting business. Conversely, the owner of such intellectual property would save that amount or be relieved from making those royalty payments. We estimated supportable royalty rates for the technology and selected a pre-tax royalty rate of 15%.
	A discount rate of 17% was utilized, which reflects the estimated 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 a rate of 36.5%, and a discounted tax amortization benefit was added to the fair value of the asset under the assumption that the technology would be amortized for tax purposes over a period of 15 years.
	We have estimated the remaining useful life for the acquired developed technology to be 5 years.
	Pro Forma Results and Acquisition-related Costs
	Pro forma financial results for the acquisition of DWA completed in January 2015 have not been presented since the acquisition was not material to our financial results.
	Acquisition-related costs for the acquisition of DWA were immaterial.

Goodwill_and_Purchased_Intangi

Goodwill and Purchased Intangible Assets	3 Months Ended
	Mar. 31, 2015
Goodwill and Purchased Intangible Assets [Abstract]
Goodwill and Purchased Intangible Assets
	5. Goodwill and Purchased Intangible Assets
	Goodwill
	The following table presents the changes in goodwill by business segment during the three months ended March 31, 2015:
			Market Services		Listing Services		Information Services		Technology Solutions		Total
			(in millions)
	Balance at December 31, 2014		$	3,081	$	114	$	1,794	$	549	$	5,538
	Goodwill acquired			-		-		111		-		111
	Foreign currency translation adjustment			-158		-11		-103		-27		-299
	Balance at March 31, 2015		$	2,923	$	103	$	1,802	$	522	$	5,350
	The goodwill acquired for Information Services shown above relates to our acquisition of DWA in January 2015. See Note 4, “Acquisition,” for further discussion.
	As of March 31, 2015, the amount of goodwill that is expected to be deductible for tax purposes in future periods is $898 million, of which $525 million is related to our acquisition of certain assets and assumption of certain liabilities of the eSpeed business, or eSpeed, $273 million is related to our acquisition of the Investor Relations, Public Relations and Multimedia Solutions businesses of Thomson Reuters, or the TR Corporate businesses, and $38 million is related to our acquisition of DWA.
	Goodwill represents the excess of the purchase price over the value assigned to the net tangible and 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 three months ended March 31, 2015 and 2014; however, events such as economic weakness or unexpected significant declines in operating results of a reporting unit may result in goodwill impairment charges in the future.
	Purchased Intangible Assets
	The following table presents details of our total purchased intangible assets, both finite- and indefinite-lived:
			31-Mar-15								31-Dec-14
			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		$	39	$	-18	$	21		5	$	35	$	-16	$	19		5
	Customer relationships			1,038		-343		695		20		1,009		-329		680		20
	Other			5		-3		2		9		5		-3		2		9
	Foreign currency translation adjustment			-138		39		-99				-94		26		-68
	Total finite-lived intangible assets		$	944	$	-325	$	619			$	955	$	-322	$	633
	Indefinite-Lived Intangible Assets
	Exchange and clearing registrations		$	790	$	-	$	790			$	790	$	-	$	790
	Trade names			745		-		745				756		-		756
	Licenses			51		-		51				51		-		51
	Foreign currency translation adjustment			-210		-		-210				-153		-		-153
	Total indefinite-lived intangible assets		$	1,376	$	-	$	1,376			$	1,444	$	-	$	1,444
	Total intangible assets		$	2,320	$	-325	$	1,995			$	2,399	$	-322	$	2,077
	Amortization expense for purchased finite-lived intangible assets was $15 million for the three months ended March 31, 2015 and $18 million for the three months ended March 31, 2014.
	The estimated future amortization expense (excluding the impact of foreign currency translation adjustment) of purchased finite-lived intangible assets as of March 31, 2015 is as follows:
			(in millions)
	2015(1)		$	50
	2016			66
	2017			64
	2018			61
	2019			47
	2020 and thereafter			430
	Total		$	718
		-1		Represents the estimated amortization to be recognized for the remaining nine months of 2015.
	Intangible Asset Impairment Charge
	In connection with our global rebranding initiative, we decided to change our company name from The NASDAQ OMX Group, Inc. to Nasdaq, Inc., pending regulatory approval. In connection with this action, we decided to discontinue the use of the OMX trade name and recorded a pre-tax, non-cash impairment charge of $119 million because we no longer attribute any material value to the trade name.  The impairment charge did not impact the company's consolidated cash flows, liquidity, or capital resources. This charge is recorded in restructuring charges in the Condensed Consolidated Statements of Income for the three months ended March 31, 2015.

Investments

Investments	3 Months Ended
	Mar. 31, 2015
Investments [Abstract]
Investments	6. Investments
	Trading Securities
	Trading securities, which are included in financial investments, at fair value in the Condensed Consolidated Balance Sheets, were $181 million as of March 31, 2015 and $171 million as of December 31, 2014. These securities are primarily comprised of highly rated European government debt securities, of which $164 million as of March 31, 2015 and $159 million as of December 31, 2014, are assets utilized to meet regulatory capital requirements primarily for our clearing operations at Nasdaq Nordic Clearing.
	Equity Method Investments
	The carrying amounts of our equity method investments totaled $67 million as of March 31, 2015 and $25 million as of December 31, 2014 and are included in other non-current assets in the Condensed Consolidated Balance Sheets. The increase in the first quarter of 2015 was primarily due to our capital contribution of $30 million to The Options Clearing Corporation, or OCC. See below for further discussion. As of March 31, 2015, in addition to our equity method investment in OCC, our equity method investments primarily included equity interests in EuroCCP N.V. and The Order Machine, or TOM. As of December 31, 2014, our equity method investments consisted primarily of our equity interests in EuroCCP N.V. and TOM.
	Net income recognized from our equity interest in the earnings and losses of these equity method investments was $14 million for the three months ended March 31, 2015 and was immaterial for the three months ended March 31, 2014. The increase is primarily due to income recognized from our equity method investment in OCC. We were not able to determine what our share of OCC’s income was for the year ended December 31, 2014 until the first quarter of 2015, when OCC financial statements were made available to us. As a result, we recorded other income of $13 million in the first quarter of 2015 relating to our share of OCC’s income for the year ended December 31, 2014.
	Capital Contribution to The Options Clearing Corporation
	In March 2015, in connection with being designated systemically important by the Financial Stability Oversight Council, OCC implemented a capital plan under which the options exchanges that are OCC’s stockholders made new capital contributions to OCC, committed to make further capital contributions in the future under certain specified circumstances, and received certain commitments from OCC with respect to future dividend payments and related matters. Certain aspects of the OCC capital plan require approval by the SEC. Under the OCC capital plan, OCC's existing exchange stockholders, including Nasdaq, each contributed a pro-rata share of $150 million in new equity capital. Nasdaq’s capital contribution was $30 million. OCC’s exchange stockholders also committed to provide, as may become necessary from time to time, additional replenishment capital on a pro-rata basis if certain capital thresholds are triggered. For its part, OCC adopted specific policies with respect to fees, customer refunds and stockholder dividends, which envision an annual dividend payment to its stockholders 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 (with such customer refunds generally to constitute 50% of the portion of OCC’s pre-tax income that exceeds OCC’s capital requirements). After the SEC staff approved the OCC capital plan and the stockholders made their capital contributions, the plan’s further effectiveness was suspended under the applicable SEC rules because certain unrelated parties petitioned the full Commission to reconsider the capital plan’s approval. If the SEC staff’s approval is reversed or the suspension of the capital plan’s effectiveness is not lifted in a timely manner, then the transaction may be reversed and the 2015 capital contributions returned to stockholders.
	Cost Method Investments
	The carrying amounts of our cost method investments totaled $132 million as of March 31, 2015 and $138 million as of December 31, 2014 and are included in other non-current assets in the Condensed Consolidated Balance Sheets. As of March 31, 2015 and December 31, 2014, our cost method investments represent our 5% ownership interest in Borsa Istanbul and our 5% ownership interest in LCH.Clearnet Group Limited, or LCH.
	The Borsa Istanbul shares, which were issued to us in the first quarter of 2014, are part of the consideration to be received under a market technology agreement. This investment has a cost basis of $75 million which is guaranteed to us via a put option negotiated as part of the market technology agreement.

Deferred_Revenue

Deferred Revenue	3 Months Ended
	Mar. 31, 2015
Deferred Revenue [Abstract]
Deferred Revenue	7. Deferred Revenue
	Deferred revenue represents consideration received that is yet to be recognized as revenue. At March 31, 2015, we estimate that our deferred revenue, which is primarily Listing Services and Technology Solutions revenues, will be recognized in the following years:
			Initial Listing Revenues		Listing of Additional Shares Revenues		Annual Renewal and Other Revenues		Technology Solutions Revenues(2)		Total
			(in millions)
	Fiscal year ended:
	2015(1)		$	11	$	24	$	166	$	58	$	259
	2016			13		25		1		29		68
	2017			11		16		-		26		53
	2018			9		6		-		21		36
	2019			7		-		-		19		26
	2020 and thereafter			3		-		-		47		50
			$	54	$	71	$	167	$	200	$	492
		-1		Represents deferred revenue that is anticipated to be recognized over the remaining nine months of 2015.
		-2		The timing of recognition of our deferred Technology Solutions revenues is primarily dependent upon the completion of customization and any significant modifications made pursuant to existing Market Technology contracts and the timing of Corporate Solutions subscription-based contracts. As such, as it relates to Market Technology revenues, the timing represents our best estimate.
	The changes in our deferred revenue during the three months ended March 31, 2015 and 2014 are reflected in the following table.
			Initial Listing Revenues		Listing of Additional Shares Revenues		Annual Renewal and Other Revenues		Technology Solutions Revenues(2)		Total
			(in millions)
	Balance at January 1, 2015		$	54	$	78	$	13	$	247	$	392
	Additions(1)			4		3		218		161		386
	Amortization(1)			-4		-10		-63		-192		-269
	Translation adjustment			-		-		-1		-16		-17
	Balance at March 31, 2015		$	54	$	71	$	167	$	200	$	492
	Balance at January 1, 2014		$	41	$	75	$	20	$	158	$	294
	Additions(1)			5		10		181		225		421
	Amortization(1)			-3		-10		-58		-145		-216
	Translation adjustment			-		-		-		-1		-1
	Balance at March 31, 2014		$	43	$	75	$	143	$	237	$	498
		-1		The additions and amortization for initial listing revenues, listing of additional shares revenues and annual renewal and other revenues primarily reflect revenues from our U.S. Listing Services business. The additions to Technology Solutions revenues during the three months ended March 31, 2014 include $75 million related to the Borsa Istanbul market technology agreement.  See “Cost Method Investments,” of Note 6, “Investments,” for further discussion.
		-2		Technology Solutions deferred revenues primarily include revenues from our Market Technology delivered client contracts in the support phase charged during the period and our Corporate Solutions subscription based contracts, which are primarily billed quarterly in advance. For our Market Technology contracts, where customization and significant modifications to the software are made to meet the needs of our customers, total revenues, as well as costs incurred, are deferred until significant modifications are completed and delivered. Once delivered, deferred revenue and the related deferred costs are recognized over the post contract support period. For these Market Technology contracts, we have included the deferral of costs in other current assets and other non-current assets in the Condensed Consolidated Balance Sheets. The amortization of Technology Solutions deferred revenue primarily includes revenues earned from Market Technology client contracts and Corporate Solutions subscription based contracts recognized during the period.

Employee_Benefits

Employee Benefits	3 Months Ended
	Mar. 31, 2015
Employee Benefits [Abstract]
Employee Benefits	9. Employee Benefits
	U.S. Defined-Benefit Pension and Supplemental Executive Retirement Plans
	We maintain non-contributory, defined-benefit pension plans, non-qualified supplemental executive retirement plans, or SERPs, for certain senior executives and 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.
	Components of Net Periodic Benefit Cost
	The following table sets forth the components of net periodic pension, SERP and post-retirement benefits costs for the Nasdaq Benefit Plans recognized in compensation and benefits expense in the Condensed Consolidated Statements of Income:
		Three Months Ended March 31,
		2015		2014
		(in millions)
	Components of net periodic benefit cost:
	Interest cost	$	1	$	2
	Expected return on plan assets		-1		-1
	Recognized net actuarial loss		1		-
	Net periodic benefit cost	$	1	$	1
	Non-U.S. Benefit Plans
	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. These costs are included in compensation and benefits expense in the Condensed Consolidated Statements of Income and were $5 million for both the three months ended March 31, 2015 and 2014.
	U.S. Defined Contribution Savings Plan
	We sponsor a voluntary defined contribution savings plan, or 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 Condensed Consolidated Statements of Income was $3 million for the three months ended March 31, 2015 and $2 million for the three months ended March 31, 2014.
	Prior to 2015, we had a profit-sharing contribution feature to our 401(k) Plan which allowed eligible U.S. employees to receive employer retirement contributions, or ERCs, when we met our annual corporate goals. In addition, we had a supplemental ERC for select highly compensated employees whose ERCs were limited by the annual Internal Revenue Service compensation limit. In December 2013, we announced changes to the ERC program. In 2014, we reduced the basic ERC contribution for all plan participants and, effective January 1, 2015, the ERC plan was discontinued and no future contributions will be made.
	Employee Stock Purchase Plan
	We have an employee stock purchase plan, or ESPP, under which approximately 2.8 million shares of our common stock have been reserved for future issuance as of March 31, 2015.
	Our ESPP allows eligible U.S. and non-U.S. 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 Condensed Consolidated Statements of Income and was $1 million for both the three months ended March 31, 2015 and 2014.

ShareBased_Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2015
Share-Based Compensation [Abstract]
Share-Based Compensation	10. Share-Based Compensation
	We have a share-based compensation program that provides our board of directors broad discretion in creating employee equity incentives. Share-based awards, or equity awards, granted under this program include stock options, restricted stock (consisting of restricted stock units), and performance share units, or PSUs. Grants of equity awards are designed to reward employees for their long-term contributions and provide incentives for them to remain with us. For accounting purposes, we consider PSUs to be a form of restricted stock.
	Restricted stock is generally time-based and vests over two- to five-year periods beginning on the date of the grant. Stock options are also generally time-based and expire ten years from the grant date. Stock option and restricted stock awards granted prior to 2014 generally included performance-based accelerated vesting features based on achievement of specific levels of corporate performance. If Nasdaq exceeded the applicable performance parameters, the grants vest on the third anniversary of the grant date, if Nasdaq met the applicable performance parameters, the grants vest on the fourth anniversary of the grant date, and if Nasdaq did not meet the applicable performance parameters, the grants vest on the fifth anniversary of the grant date. Beginning in 2014, restricted stock awards granted vest 25% on the second anniversary of the grant date, 25% on the third anniversary of the grant date, and 50% on the fourth anniversary of the grant date. The grant date fair value of restricted stock awards is based on the closing price at the date of grant less the present value of future cash dividends.
	PSUs are based on performance measures that impact the amount of shares that each recipient will receive upon vesting. PSUs are granted at the fair market value of our stock on the grant date and compensation cost is recognized over the performance period and, in certain cases, an additional vesting period. For each grant of PSUs, an employee may receive from 0% to 150% of the target amount granted, depending on the achievement of performance measures. We report the target number of PSUs granted, unless we have determined that it is more likely than not, based on the actual achievement of performance measures, that an employee will receive a different amount of shares underlying the PSUs, in which case we report the amount of shares the employee is likely to receive.
	We also have a performance-based long-term incentive program for our chief executive officer, presidents, executive vice presidents and senior vice presidents that focuses on total shareholder return, or TSR. This program represents 100% of our chief executive officer’s, presidents’ and executive vice presidents’ long-term stock-based compensation and 50% of our senior vice presidents’ long-term stock-based compensation. Under the program, each individual receives PSUs with a three-year cumulative performance period that vest at the end of the performance period. Performance will be determined by comparing Nasdaq’s TSR to two peer groups, each weighted 50%. The first peer group consists of exchange companies, and the second peer group consists of all companies in the Standard & Poor’s 500 Index. 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% and 200% 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% of the number of PSUs granted. We estimate the fair value of PSU’s granted under the TSR program using the Monte Carlo simulation model, as these awards contain a market condition. The following weighted-average assumptions were used to determine the weighted-average fair values of the PSU awards granted under the TSR program for the three months ended March 31, 2015 and 2014:
			Three Months Ended March 31,
			2015			2014
	Weighted-average risk free interest rate			0.81%			0.79%
	Expected volatility(1)			21.5%			29.1%
	Grant date share price		$	50.94		$	36.94
	Annual dividend		$	0.60		$	0.60
	Weighted-average fair value at grant date		$	64.03		$	43.13
		-1		We use historic volatility for PSU awards issued under the TSR program, as implied volatility data could not be obtained for all the companies in the peer groups used for relative performance measurement within the TSR program.
	Summary of 2015 Equity Awards
	In March 2015, we granted restricted stock to most active employees. During 2015, certain officers received grants of 595,732 PSUs. Of these PSUs granted, 416,380 units are subject to the performance measures and vesting schedules of the TSR program as discussed above, and the remaining 179,352 units are subject to a one-year performance period and generally vest ratably on an annual basis from December 31, 2016 through December 31, 2018. See “Summary of Restricted Stock and PSU Activity” below for further discussion.
	During 2014, certain grants of PSUs with a one-year performance period exceeded the applicable performance parameters. As a result, an additional 21,429 units were considered granted in the first quarter of 2015.
	Certain grants of PSUs that were issued in 2012 under the TSR program with a three-year performance period exceeded the applicable performance parameters. As a result, an additional 224,805 units were considered granted in the first quarter of 2015.
	Common Shares Available Under Our Equity Plan
	As of March 31, 2015, we had approximately 6.5 million shares of common stock authorized for future issuance under Nasdaq’s Equity Incentive Plan.
	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 three months ended March 31, 2015 and 2014 in the Condensed Consolidated Statements of Income:
			Three Months Ended March 31,
			2015			2014
			(in millions)
	Share-based compensation expense before income taxes		$	14		$	14
	Income tax benefit			-6			-6
	Share-based compensation expense after income taxes		$	8		$	8
	Summary of Stock Option Activity
	A summary of stock option activity for the three months ended March 31, 2015 is as follows:
			Number of Stock Options(1)			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term			Aggregate Intrinsic Value
								(in years)			(in millions)
	Outstanding at January 1, 2015			3,316,782		$	27.56		3.77		$	68
	Exercised			-232,459			25.78
	Outstanding at March 31, 2015			3,084,323		$	27.69		3.46		$	72
	Exercisable at March 31, 2015			3,084,323		$	27.69		3.46		$	72
		-1		No stock option awards were granted during the three months ended March 31, 2015.
	We received net cash proceeds of $6 million from the exercise of 232,459 stock options during the three months ended March 31, 2015 and received net cash proceeds of $7 million from the exercise of 367,115 stock options during the three months ended March 31, 2014. We present excess tax benefits from the exercise of stock options, if any, as financing cash flows.
	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 March 31, 2015 of $50.94 and the exercise price, times the number of shares) based on stock options with an exercise price less than Nasdaq’s closing price of $50.94 as of March 31, 2015, 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 March 31, 2015 was 3.1 million.
	As of March 31, 2014, 4.5 million outstanding stock options were exercisable and the weighted-average exercise price was $25.72.
	The total pre-tax intrinsic value of stock options exercised was $5 million for the three months ended March 31, 2015 and $7 million for the three months ended March 31, 2014.
	Total fair value of stock options vested was $11 million for the three months ended March 31, 2014.
	Summary of Restricted Stock and PSU Activity
	The following table summarizes our restricted stock and PSU activity for the three months ended March 31, 2015:
			Restricted Stock					PSUs
			Number of Awards			Weighted-Average Grant Date Fair Value		Number of Awards			Weighted-Average Grant Date Fair Value
	Unvested balances at January 1, 2015			3,193,230		$	30.99		2,212,607		$	32.69
	Granted			747,958	-1		49.22		841,966	-2		49.16
	Vested			-132,157			26.94		-837,109			22.50
	Forfeited			-71,543			32.37		-37,947			35.77
	Unvested balances at March 31, 2015			3,737,488		$	33.74		2,179,517		$	44.81
		-1		Primarily reflects our company-wide equity grant issued in March 2015, as discussed above.
		-2		PSUs granted in 2015 reflect awards issued to certain officers, as described above.
	At March 31, 2015, $132 million of total unrecognized compensation cost related to restricted stock and PSUs is expected to be recognized over a weighted-average period of 1.8 years.

Nasdaq_Stockholders_Equity

Nasdaq Stockholders’ Equity	3 Months Ended
	Mar. 31, 2015
Nasdaq Stockholders’ Equity [Abstract]
Nasdaq Stockholders' Equity	11. Nasdaq Stockholders’ Equity
	Common Stock
	At March 31, 2015, 300,000,000 shares of our common stock were authorized, 171,527,299 shares were issued and 168,927,790 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 Condensed Consolidated Balance Sheets. When treasury shares are reissued, they are recorded at the average cost of the treasury shares acquired. We held 2,599,509 shares of common stock in treasury as of March 31, 2015 and 1,530,041 shares as of December 31, 2014.
	Share Repurchase Program
	In the third quarter of 2012, our board of directors authorized the repurchase of up to $300 million of our outstanding common stock and in the fourth quarter 2014, our board of directors authorized the repurchase of up to an additional $500 million of our outstanding common stock under our share repurchase program.
	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 funded from existing cash balances. The share repurchase program may be suspended, modified or discontinued at any time.
	During the first three months of 2015, we repurchased 599,951 shares of our common stock at an average price of $50.08, for an aggregate purchase price of $30 million. Most shares repurchased under the share repurchase program are retired and cancelled, and the remaining shares are available for general corporate purposes. As of March 31, 2015, the remaining amount authorized for share repurchases under the program was $507 million.
	Other Repurchases of Common Stock
	During the three months ended March 31, 2015, we repurchased 469,517 shares of our common stock in settlement of employee tax withholding obligations due upon the vesting of restricted stock.
	Cash Dividends on Common Stock
	During the three months ended March 31, 2015, our board of directors declared the following cash dividends:
	Declaration Date		Dividend Per		Record Date	Total Amount(1)		Payment Date
			Common Share
						(in millions)
	29-Jan-15		$	0.15	13-Mar-15	$	25	27-Mar-15
		-1		This amount was recorded in retained earnings in the Condensed Consolidated Balance Sheets at March 31, 2015.
	In April 2015, the board of directors declared a regular quarterly cash dividend of $0.25 per share on our outstanding common stock, reflecting a 67% increase from our prior quarterly cash dividend of $0.15. The dividend is payable on June 26, 2015 to shareholders of record at the close of business on June 12, 2015. Future declarations of quarterly dividends and the establishment of future record and payment dates are subject to approval by the board of directors.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Share	12. Earnings Per Share
	The following table sets forth the computation of basic and diluted earnings per share:
		Three Months Ended March 31,
		2015		2014
		(in millions, except share and per share amounts)
	Numerator:
	Net income attributable to common shareholders	$	9	$	103
	Denominator:
	Weighted-average common shares outstanding for basic earnings per share		168,985,956		169,595,951
	Weighted-average effect of dilutive securities:
	Employee equity awards		3,691,163		4,070,605
	Weighted-average common shares outstanding for diluted earnings per share		172,677,119		173,666,556
	Basic and diluted earnings per share:
	Basic earnings per share	$	0.05	$	0.61
	Diluted earnings per share	$	0.05	$	0.59
	Stock options to purchase 3,084,323 shares of common stock and 5,917,005 shares of restricted stock and PSUs were outstanding at March 31, 2015. For the three months ended March 31, 2015, we included all of the outstanding stock options and 4,573,314 shares of restricted stock and PSUs in the computation of diluted earnings per share, on a weighted-average basis, as their inclusion was dilutive. The remaining shares of restricted stock and PSUs are antidilutive, and as such, they were properly excluded.
	Stock options to purchase 4,532,006 shares of common stock and 5,938,944 shares of restricted stock and PSUs were outstanding at March 31, 2014. For the three months ended March 31, 2014, we included 4,398,297 of the outstanding stock options and 4,262,190 shares of restricted stock and PSUs in the computation of diluted earnings per share, on a weighted-average basis, as their inclusion was dilutive. The remaining stock options and shares of restricted stock and PSUs are antidilutive, and as such, they were properly excluded.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments	3 Months Ended
	Mar. 31, 2015
Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Instruments	13. Fair Value of Financial Instruments
	Fair Value Measurement—Definition and Hierarchy
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability, or the exit price, in an orderly transaction between market participants at the measurement date. 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.
	There were no transfers between Level 1 and Level 2 of the fair value hierarchy as of March 31, 2015 and December 31, 2014. The following table presents for each of the above hierarchy levels, our financial assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014.
			31-Mar-15
			Total		Level 1		Level 2		Level 3
			(in millions)
	Financial Assets Measured at Fair Value on a Recurring Basis
	Financial investments, at fair value(1)		$	194	$	181	$	13	$	-
	Default fund and margin deposit investments(2)			2,494		692		1,802		-
	Total		$	2,688	$	873	$	1,815	$	-
			31-Dec-14
			Total		Level 1		Level 2		Level 3
			(in millions)
	Financial Assets Measured at Fair Value on a Recurring Basis
	Financial investments, at fair value(1)		$	174	$	171	$	3	$	-
	Default fund and margin deposit investments(2)			2,148		664		1,484		-
	Total		$	2,322	$	835	$	1,487	$	-
		-1		As of March 31, 2015 and December 31, 2014, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. Of these securities, $164 million as of March 31, 2015 and $159 million as of December 31, 2014 are assets utilized to meet regulatory capital requirements, primarily for the clearing operations of Nasdaq Nordic Clearing. As of March 31, 2015 and December 31, 2014, Level 2 financial investments, at fair value were primarily comprised of available-for-sale investment securities in short-term commercial paper.
		-2		Default fund and margin deposit investments include cash contributions invested by Nasdaq Nordic Clearing, in accordance with its investment policy, either in highly rated European, and to a lesser extent, U.S. government debt securities or reverse repurchase agreements with highly rated government debt securities as collateral. Of the total balance of $2,635 million recorded in the Condensed Consolidated Balance Sheets as of March 31, 2015, $692 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and $1,802 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance is held in cash. Of the total balance of $2,194 million recorded in the Condensed Consolidated Balance Sheets as of December 31, 2014, $664 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and term deposits and $1,484 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance was held in cash.
	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, and certain other current liabilities.
	In addition, our investments in OCC, EuroCCP N.V. and TOM are accounted for under the equity method of accounting and our investments in LCH and Borsa Istanbul are carried at cost. See “Equity Method Investments” and “Cost 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, utilizing discounted cash flow analyses for our floating rate debt and prevailing market rates for our fixed rate debt, was $2.5 billion at both March 31, 2015 and December 31, 2014. The discounted cash flow analyses are based on borrowing rates currently available to us for debt with similar terms and maturities. Our fixed rate and our floating rate debt is categorized as Level 2 in the fair value hierarchy. For further discussion of our debt obligations, see Note 8, “Debt Obligations.”

Clearing_Operations

Clearing Operations	3 Months Ended
	Mar. 31, 2015
Clearing Operations [Abstract]
Clearing Operations	14. Clearing Operations
	Nordic Clearing
	Nasdaq Nordic Clearing is authorized and supervised as a European multi-asset clearinghouse by the Swedish Financial Supervisory Authority, or SFSA, and is authorized to conduct clearing operations in Norway by the Norwegian Ministry of Finance. The clearinghouse acts as the central counterparty, or CCP, for exchange and over-the-counter, or OTC, trades in equity derivatives, fixed income derivatives, power derivatives, carbon derivatives, resale and repurchase contracts, freight 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 Nordic Clearing is the legal counterparty for, and guarantees the fulfillment of, each contract cleared. These contracts are not used by Nasdaq Nordic Clearing for the purpose of trading on its own behalf. As the legal counterparty of each transaction, Nasdaq Nordic Clearing bears the counterparty risk between the purchaser and seller in the contract. In its guarantor role, Nasdaq Nordic Clearing has precisely equal and offsetting claims to and from clearing members on opposite sides of each contract, standing as an intermediary on every contract cleared. In accordance with the rules and regulations of Nasdaq Nordic Clearing, clearing members’ open positions are aggregated to create a single portfolio for which default fund and margin collateral requirements are calculated. See “Default Fund Contributions” and “Margin Deposits” below for further discussion of Nasdaq Nordic Clearing’s default fund and margin requirements.
	Nasdaq Nordic 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 Nordic Clearing and its clearing members must contribute to the total regulatory capital related to the clearing operations of Nasdaq Nordic 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 Nordic Clearing members with regard to total regulatory capital required. See “Default Fund Contributions” below for further discussion of Nasdaq Nordic 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 Nordic Clearing and its clearing members.
	Default Fund Contributions and Margin Deposits
	As of March 31, 2015, clearing member default fund contributions and margin deposits were as follows:
			31-Mar-15
			Cash Contributions(1)		Non-Cash Contributions		Total Contributions
			(in millions)
	Default fund contributions		$	282	$	75	$	357
	Margin deposits			2,353		5,269		7,622
	Total		$	2,635	$	5,344	$	7,979
		-1		As of March 31, 2015, in accordance with its investment policy, Nasdaq Nordic Clearing has invested cash contributions of $1,802 million in reverse repurchase agreements and $692 million in highly rated European, and to a lesser extent, U.S. government debt securities. The remainder of this balance is held in cash.
	Default Fund Contributions
	Contributions made 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 Nordic Clearing, in accordance with its investment policy, either in highly rated government debt securities or reverse repurchase agreements with highly rated government debt securities as collateral. Clearing members’ cash contributions are included in default funds and margin deposits in the Condensed 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 Nordic Clearing. Non-cash contributions are pledged assets that are not recorded in the Condensed Consolidated Balance Sheets as Nasdaq Nordic 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 Nordic Clearing’s name for the benefit of the clearing members and are immediately accessible by Nasdaq Nordic Clearing in the event of a default. In addition to clearing members’ required contributions to the default funds, Nasdaq Nordic Clearing is also required to contribute capital to the default funds and overall regulatory capital as specified under its clearinghouse rules. As of March 31, 2015, Nasdaq Nordic Clearing committed capital totaling $126 million to the member sponsored default funds and overall regulatory capital, in the form of government debt securities, which are recorded as financial investments, at fair value in the Condensed Consolidated Balance Sheets. The combined regulatory capital of the clearing members and Nasdaq Nordic Clearing will serve to secure the obligations of a clearing member and may be used to cover losses sustained by a clearing member in the event of a default.
	Margin Deposits
	Nasdaq Nordic 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 as needed, which is in addition to the initial margin. See “Default Fund Contributions” above for further discussion of cash and non-cash contributions.
	Nasdaq Nordic Clearing maintains and manages all cash deposits related to margin collateral. All risks and rewards of collateral ownership, including interest, belong to Nasdaq Nordic Clearing. These cash deposits are recorded in default funds and margin deposits in the Condensed Consolidated Balance Sheets as both a current asset and current liability. Pledged margin collateral is not recorded in our Condensed 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 Nordic Clearing’s name for the benefit of the clearing members and are immediately accessible by Nasdaq Nordic Clearing in the event of a default.
	Nasdaq Nordic 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 Nordic Clearing the ability to mitigate the risk of a clearing member defaulting due to exceptionally large losses. In the event of a default, Nasdaq Nordic Clearing can access the defaulting member’s margin deposits to cover the defaulting member’s losses.
	Regulatory Capital and Risk Management Calculations
	Nasdaq Nordic Clearing manages risk through a comprehensive counterparty risk management framework, which is comprised of policies, procedures, standards and resources. The level of regulatory capital is determined in accordance with Nasdaq Nordic 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 Nordic Clearing is the legal counterparty for each contract traded and thereby guarantees the fulfillment of each contract. Nasdaq Nordic 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, the estimated liability was nominal and no liability was recorded as of March 31, 2015.
	The market value of derivative contracts outstanding prior to netting was as follows:
			31-Mar-15
			(in millions)
	Commodity and seafood options, futures and forwards(1)(2)(3)		$	1,204
	Fixed-income options and futures(2)(3)			1,088
	Stock options and futures(2)(3)			178
	Index options and futures(2)(3)			222
	Total		$	2,692
		-1		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.
		-2		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.
		-3		We determined the fair value of our futures contracts based upon quoted market prices and average quoted market yields.
	The total number of derivative contracts cleared through Nasdaq Nordic Clearing for the three months ended March 31, 2015 and 2014 was as follows:
			31-Mar-15		31-Mar-14
	Commodity and seafood options, futures and forwards(1)			620,417		634,742
	Fixed-income options and futures			4,449,856		5,761,558
	Stock options and futures			9,981,753		8,809,147
	Index options and futures			13,115,693		9,970,534
	Total			28,167,719		25,175,981
		-1		The total volume in cleared power related to commodity contracts was 363 Terawatt hours (TWh) for the three months ended March 31, 2015 and 429 TWh for the three months ended March 31, 2014.
	The outstanding contract value of resale and repurchase agreements was $3.6 billion as of March 31, 2015 and $3.9 billion as of March 31, 2014. The total number of contracts cleared was 1,582,082 for the three months ended March 31, 2015 and was 1,209,945 for the three months ended March 31, 2014.
	Power of Assessment
	To further strengthen the contingent financial resources of the clearinghouse, Nasdaq Nordic 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% 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 Nordic Clearing, which totaled $18 million at March 31, 2015;
		·		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 for the market where the loss occurred (i.e., the financial, commodities, or seafood market), which includes capital contributions of both the clearing members and Nasdaq Nordic Clearing on a pro-rata basis;
		·		senior capital contributed to each specific market by Nasdaq Nordic Clearing, calculated in accordance with clearinghouse rules, which totaled $35 million at March 31, 2015; and
		·		mutualized default fund, which includes capital contributions of both the clearing members and Nasdaq Nordic Clearing on a pro-rata basis.
	If additional funds are needed after utilization of the mutualized default fund, then Nasdaq Nordic 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.

Commitments_Contingencies_and_

Commitments, Contingencies and Guarantees	3 Months Ended
	Mar. 31, 2015
Commitments, Contingencies and Guarantees [Abstract]
Commitments, Contingencies and Guarantees	15. 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 14, “Clearing Operations,” we have obtained financial guarantees and credit facilities which are guaranteed by us through counter indemnities, to provide further liquidity and default protection related to our clearing businesses. Financial guarantees issued to us totaled $14 million at both March 31, 2015 and December 31, 2014. At March 31, 2015, credit facilities, which are available in multiple currencies, primarily Swedish Krona, totaled $179 million in available liquidity, none of which was utilized. At December 31, 2014, credit facilities, which are available in multiple currencies, primarily Swedish Krona, totaled $236 million ($197 million in available liquidity and $39 million for default protection), of which $7 million was utilized.
	Execution Access LLC is an introducing broker which operates the eSpeed trading platform for U.S. Treasury securities. Execution Access has a clearing arrangement with Cantor Fitzgerald & Co., or Cantor Fitzgerald. As of March 31, 2015, we have contributed $19 million of clearing deposits to Cantor Fitzgerald in connection with this clearing arrangement. These deposits are recorded in other current assets in our Condensed Consolidated Balance Sheets. Some of the trading activity in Execution Access is cleared by Cantor Fitzgerald through the Fixed Income Clearing Corporation. 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 one business day. All of Execution Access’ obligations under the clearing arrangement with Cantor Fitzgerald are guaranteed by Nasdaq. Counterparties that do not clear through the Fixed Income Clearing Corporation are required to post collateral, provide principal letters, or provide other forms of credit enhancement to Execution Access for the purpose of mitigating counterparty risk.
	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 Condensed Consolidated Balance Sheets for these arrangements.
	Lease Commitments
	We lease some of our office space and equipment 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
	We have provided other guarantees of $12 million as of March 31, 2015 and $13 million at December 31, 2014. These guarantees are primarily related to obligations for our rental and leasing contracts as well as performance guarantees on certain Market Technology contracts related to the delivery of software technology and support services. We have received financial guarantees from various financial institutions to support the above guarantees.
	In September 2014, we provided a guarantee related to lease obligations for The Nasdaq Entrepreneurial Center Inc., or the Entrepreneurial Center, which is scheduled to open in 2015. The Entrepreneurial Center will be a not-for-profit organization designed to convene, connect and engage aspiring and current entrepreneurs. This entity is not included in the condensed 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 Condensed Consolidated Balance Sheets for the above guarantees.
	In connection with the launch of Nasdaq NLX, we entered into agreements with certain members which may require us to make payments if certain financial goals are achieved. Since the amount of these payments is not currently probable and cannot be quantified as of March 31, 2015, no contingent liability is recorded in the Condensed Consolidated Balance Sheets for these payments.
	Non-Cash Contingent Consideration
	As part of the eSpeed purchase price consideration, 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.
	Other Transactions
	OCC
	In March 2015, in connection with being designated systemically important by the Financial Stability Oversight Council, OCC implemented a capital plan under which the options exchanges that are OCC’s stockholders made new capital contributions to OCC, committed to make further capital contributions in the future under certain specified circumstances, and received certain commitments from OCC with respect to future dividend payments and related matters. Certain aspects of the OCC capital plan require approval by the SEC. Under the OCC capital plan, OCC's existing exchange stockholders, including Nasdaq, each contributed a pro-rata share of $150 million in new equity capital. Nasdaq’s capital contribution was $30 million. OCC’s exchange stockholders also committed to provide, as may become necessary from time to time, additional replenishment capital on a pro-rata basis if certain capital thresholds are triggered. For its part, OCC adopted specific policies with respect to fees, customer refunds and stockholder dividends, which envision an annual dividend payment to its stockholders 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 (with such customer refunds generally to constitute 50% of the portion of OCC’s pre-tax income that exceeds OCC’s capital requirements). After the SEC staff approved the OCC capital plan and the stockholders made their capital contributions, the plan’s further effectiveness was suspended under the applicable SEC rules because certain unrelated parties petitioned the full Commission to reconsider the capital plan’s approval. If the SEC staff’s approval is reversed or the suspension of the capital plan’s effectiveness is not lifted in a timely manner, then the transaction may be reversed and the 2015 capital contributions returned to stockholders.
	Escrow Agreements
	In connection with a prior acquisition, we entered into an escrow agreement to secure the payment of post-closing adjustments and to ensure other closing conditions. At March 31, 2015, this escrow agreement provides for a potential future payment of $9 million and is included in other current liabilities in the Condensed Consolidated Balance Sheets.
	Routing Brokerage Activities
	One of our broker-dealer subsidiaries, Nasdaq Execution Services, LLC 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 Condensed Consolidated Balance Sheets for these arrangements.
	In March 2014, Nasdaq Execution Services began routing options and became the sole routing broker for Nasdaq’s U.S. cash equities and options exchanges. As a consequence, Nasdaq Options Services, LLC, which previously served as the routing broker for our U.S. options exchanges, became non-operational and terminated its exchange and clearinghouse memberships in March 2014.
	Litigation
	As previously disclosed, we became a party to several legal and regulatory proceedings in 2012, 2013, and 2014 relating to the Facebook IPO that occurred on May 18, 2012.
	As described in our Annual Report on Form 10-K for the year ended December 31, 2012, we are named as a defendant in a consolidated matter captioned In re Facebook, Inc., IPO Securities and Derivative Litigation, MDL No. 2389 (S.D.N.Y.). Our appeal of the district court’s order granting in part and denying in part our motion to dismiss the consolidated amended complaint is currently pending in the United States Court of Appeals for the Second Circuit, at No. 14-1457. We have reached an agreement in principle, subject to court approval, to settle these claims.
	In our Quarterly Report on Form 10-Q for the period ended March 31, 2013, we identified a demand for arbitration from a member organization seeking indemnification for alleged losses associated with the Facebook IPO. On June 18, 2013, the District Court for the Southern District of New York granted a preliminary injunction enjoining the arbitration, and the member organization appealed the order granting the injunction to the Second Circuit Court of Appeals. On October 31, 2014, the Second Circuit Court of Appeals affirmed the preliminary injunction. In April 2015, we reached an agreement to settle the claims asserted by the member organization.
	We have established a reserve of $31 million to cover the costs of these settlements. We anticipate that some or all of the amounts paid from the loss reserve will be reimbursed by applicable insurance coverage.
	We also 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 Securities Exchange Act of 1934, as amended, or the Exchange Act, and Rule 10b-5, as well as under Section 6(b) of the Exchange Act. 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. The plaintiffs filed an opposition to our motion to dismiss on March 24, 2015. Our reply is due on May 8, 2015. On January 12, 2015, the court consolidated this case in a multi-district litigation proceeding under the heading In re Barclays Liquidity Cross and High Frequency Trading Litigation, 14-md-02589 (S.D.N.Y). The consolidated cases bring claims against Barclays PLC and Barclays Capital alleging that certain marketing materials about Barclays LX contained false or misleading statements. Although the Providence matter has been consolidated with the Barclays matter, separate motions to dismiss have been filed for each case. Given the preliminary nature of the proceedings, we are unable to estimate what, if any, liability may result from this litigation. However, we believe the claims to be without merit and intend to litigate them vigorously.
	In addition, we are named as one of many exchange defendants in Lanier v. BATS Exchange Inc., et al., 14 Civ. 3745 (S.D.N.Y.), Lanier v. BATS Exchange Inc., et al., 14 Civ. 3865 (S.D.N.Y.), and Lanier v. Bats Exchange Inc., 14 Civ. 3866 (S.D.N.Y.), which were filed between May 23, 2014 and May 30, 2014 in the United States District Court for the Southern District of New York. The plaintiff is the same in each of these cases, and the three complaints contain substantially similar allegations. On behalf of a putative class of subscribers for market data provided by national exchanges, the plaintiff alleges that the exchanges provided data more quickly to certain market participants than to others, supposedly in breach of the exchanges’ plans for dissemination of market data and subscriber agreements executed under those plans. The complaint asserts contractual theories under state law based on these alleged breaches. On September 29, 2014, we filed a motion to dismiss the complaints. The court heard oral argument on the motion on January 16, 2015. On April 28, 2015, the district court entered an order dismissing the complaints with prejudice, concluding that they are foreclosed by the Exchange Act and in any event do not state a claim under the contracts.
	On February 5, 2015, I. Stephen Rabin filed a putative class action, Rabin v. John Doe Market Makers, NASDAQ OMX PHLX LLC, and NASDAQ OMX Group, Inc., No. 15-551 (E.D. Pa.), in the United States District Court for the Eastern District of Pennsylvania alleging that options traders on the Nasdaq PHLX exchange were damaged when market makers on that exchange manipulated options in advance of dividend payments on underlying stock and exchange traded funds for their personal benefit. Plaintiff further alleges that – with the assent of the Nasdaq defendants – the unidentified market maker defendants (plaintiff states an intention to seek their identities from the Nasdaq defendants in discovery) damaged other writers of call options by executing among themselves prearranged manipulative matched options trades on an underlying security immediately prior to the date for the that security’s dividend payment. The alleged class period is from February 6, 2010 through the present. Based on these allegations, plaintiff asserts claims against all defendants for securities fraud pursuant to Section 10(b) of the Securities Exchange Act and Rule 10b-5 promulgated thereunder, and for unjust enrichment. We believe the claims to be without merit and intend to litigate them vigorously.
	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.
	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.

Business_Segments

Business Segments	3 Months Ended
	Mar. 31, 2015
Business Segments [Abstract]
Business Segments	16. Business Segments
	We manage, operate and provide our products and services in four business segments: Market Services, Listing Services, Information Services and Technology Solutions. See Note 1, “Organization and Nature of Operations,” to the condensed consolidated financial statements for further discussion of our reportable segments.
	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 our management structure. Certain amounts are allocated to corporate items in our management reports based on the decision that those activities should not be used to evaluate the segment’s operating performance. Since management does not consider intangible asset amortization expense for the purpose of evaluating the performance of the business or its managers or when making decisions to allocate resources, such expenses are shown in corporate items in our management reports. See below for further discussion.
	The following table presents certain information regarding these operating segments for the three months ended March 31, 2015 and 2014.
			Market Services		Listing Services		Information Services		Technology Solutions		Corporate Items and Eliminations		Consolidated
			(in millions)
	Three Months Ended March 31, 2015
	Total revenues		$	539	$	64	$	125	$	130	$	-	$	858
	Transaction-based expenses			-351		-		-		-		-		-351
	Revenues less transaction-based expenses			188		64		125		130		-		507
	Operating income (loss)(1)		$	101	$	28	$	92	$	14	$	-208	$	27
	Three Months Ended March 31, 2014
	Total revenues		$	577	$	58	$	123	$	140	$	-	$	898
	Transaction-based expenses			-369		-		-		-		-		-369
	Revenues less transaction-based expenses			208		58		123		140		-		529
	Operating income (loss)(2)		$	105	$	22	$	92	$	13	$	-48	$	184
	(1)   Corporate items and eliminations for the three months ended March 31, 2015 include:
		·		restructuring charges of $150 million. See Note 3, “Restructuring Charges,” for further discussion;
		·		special legal expenses of $31 million;
		·		amortization expense of acquired intangible assets of $15 million; and
		·		reversal of VAT refund receivables no longer deemed collectible of $12 million.
	(2)   Corporate items and eliminations for the three months ended March 31, 2014 primarily include:
		·		merger and strategic initiatives expense of $28 million primarily related to the acquisition of the TR Corporate businesses and other strategic initiatives; and
		·		amortization expense of acquired intangible assets of $18 million.
	For further discussion of our segments’ results, see “Part I. Item 2. Management’s Discussion and Analysis of Financial     Condition and Results of Operations—Segment Operating Results.”

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Event	17. Subsequent Events
	Increase in Quarterly Cash Dividend
	In April 2015, the board of directors declared a regular quarterly cash dividend of $0.25 per share on our outstanding common stock, reflecting a 67% increase from our prior quarterly cash dividend of $0.15. See “Cash Dividends on Common Stock,” of Note 11, “Nasdaq Stockholders’ Equity,” for further discussion.
	Agreements to Settle Litigation
	In April 2015, we reached an agreement in principle, subject to court approval, to settle class-action litigation arising from the Facebook IPO in May 2012. We also reached an agreement to settle claims by a member organization arising from the Facebook IPO. See “Litigation” of Note 15, “Commitments, Contingencies and Guarantees,” to the condensed consolidated financial statements for further discussion.

Basis_of_Presentation_and_Prin1

Basis of Presentation and Principles of Consolidation (Policy)	3 Months Ended
	Mar. 31, 2015
Basis of Presentation and Principles of Consolidation [Abstract]
Basis of Accounting	The condensed consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP. The condensed consolidated financial statements 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. As permitted under U.S. GAAP, for certain equity method investments for which financial information is not sufficiently timely for us to apply the equity method of accounting currently, we record our share of the earnings or losses of the investee from the most recently available financial statements on a lag. See “Equity Method Investments,” of Note 6, “Investments,” for further discussion of our equity method investments.
	The accompanying condensed consolidated financial statements reflect all adjustments which are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. These adjustments are of a normal recurring nature. All significant intercompany accounts and transactions have been eliminated in consolidation.
	As permitted under U.S. GAAP, certain footnotes or other financial information can be condensed or omitted in the interim condensed consolidated financial statements. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in Nasdaq’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014.
	Certain prior period amounts have been reclassified to conform to the current period presentation.
	The preparation of condensed 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 condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
	We have evaluated subsequent events through the issuance date of this Quarterly Report on Form 10-Q. See Note 17, “Subsequent Events,” for further discussion.
Consolidation Policy	Certain prior period amounts have been reclassified to conform to the current period presentation.
	The preparation of condensed 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 condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
Income Tax matters	Income Tax Matters
	We use the asset and liability method to determine income taxes on all transactions recorded in the condensed consolidated financial statements. 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 condensed consolidated financial statements. Interest and/or penalties related to income tax matters are recognized in income tax expense.
	Nasdaq’s income tax provision was $5 million in the first quarter of 2015 compared with $53 million in the first quarter of 2014. The overall effective tax rate was 36% in the first quarter of 2015 and 34% in the first quarter of 2014. The higher effective tax rate in the first quarter of 2015 when compared with the same period in 2014 is primarily due to adjustments related to prior year tax liabilities which resulted in an increase to the tax provision. 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 history of pre-tax earnings and losses, are taken into account in assessing the ability to realize deferred tax assets.
	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 2011 and 2012 are currently under audit by the Internal Revenue Service and we are subject to examination for years 2008 through 2010 and 2013. Several state tax returns are currently under examination by the respective tax authorities for the years 2005 through 2013. Non-U.S. tax returns are subject to examination by the respective tax authorities for the years 2008 through 2013. We anticipate that the amount of unrecognized tax benefits at March 31, 2015 will significantly decrease in the next twelve months as we expect to settle certain tax audits. The final outcome of such audits cannot yet be determined. We anticipate that such adjustments will not have a material impact on our consolidated financial position or results of operations.
	In the fourth quarter of 2010, we received an appeal from the Finnish Tax Authority challenging certain interest expense deductions claimed by Nasdaq in Finland for the year 2008. The appeal also demanded certain penalties be paid with regard to the company’s tax return filing position. In October 2012, the Finnish Appeals Board disagreed with the company’s tax return filing position for years 2009 through 2011, even though the tax return position with respect to this deduction was previously reviewed and approved by the Finnish Tax Authority. In June 2014, the Finnish Administrative Court also disagreed with the company’s tax return filing position for these years. We have appealed this ruling to the Finnish Supreme Administrative Court and expect to receive a favorable decision. Through March 31, 2015, we have recorded tax benefits of $24 million associated with this filing position. We have paid $35 million to the Finnish tax authorities, which includes $11 million in interest and penalties. We expect the Finnish Supreme Administrative Court to agree with our position, which would result in an expected refund to Nasdaq of $30 million, which reflects the impact of foreign currency translation. If the Finnish Supreme Administrative Court disagrees with our position, we would record tax expense of $30 million, or $0.17 per diluted share.
	From 2009 through 2012, we recorded tax benefits associated with certain interest expense incurred in Sweden. Our position is supported by a 2011 ruling we received from the Swedish Supreme Administrative Court. However, under new legislation effective January 1, 2013, limitations are imposed on certain forms of interest expense. Because this legislation is unclear with regard to our ability to continue to claim such interest deductions, Nasdaq filed an application for an advance tax ruling with the Swedish Tax Council for Advance Tax Rulings. In June 2014, we received an unfavorable ruling from the Swedish Tax Council for Advance Tax Rulings. We appealed this ruling to the Swedish Supreme Administrative Court; however the Swedish Supreme Administrative Court has denied our request for a ruling based on procedural requirements. As a result of the Swedish Supreme Administrative Court’s denial to provide a ruling, we will appeal to the Lower Administrative Court. We continue to expect a favorable decision. Since January 1, 2013, we have recorded tax benefits of $35 million, or $0.20 per diluted share, related to this matter. We expect to record recurring quarterly tax benefits of $3 million to $4 million with respect to this issue for the foreseeable future.
	Other Tax Matter
	In December 2012, the Swedish Tax Agency approved our 2010 amended value added tax, or VAT, tax return and we received a cash refund for the amount claimed. In 2013, we filed amended VAT tax returns for 2011 and 2012, utilizing the same approach which was approved for the 2010 filing. We also utilized this approach in our 2013 and 2014 filings. However, even though the VAT return position was previously reviewed and approved by the Swedish Tax Agency, the Swedish Tax Agency challenged our approach. The revised position of the Swedish Tax Agency was upheld by the Lower Administrative Court during the first quarter of 2015. As a result, in the first quarter of 2015, we reversed the previously recorded benefit of $12 million, based on the court decision. We will appeal the ruling of the Lower Administrative Court to the Court of Appeals.
Recently Adopted Accounting Pronouncements	Recently Announced Accounting Pronouncements
	In April 2015, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, 2015-03, “Simplifying the Presentation of Debt Issuance Costs,” which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the debt liability rather than as an asset. The recognition and measurement guidance for debt issuance costs is not affected by this new guidance. Debt issuance costs will continue to be amortized as interest expense using the effective interest method. This guidance will be effective for us on January 1, 2016. Early adoption is permitted. The adoption of this guidance will not have a material impact on our consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers (Topic 606),” which supersedes the revenue recognition guidance in Accounting Standards Codification, or ASC, 605, “Revenue Recognition.” The new revenue recognition standard sets forth a five-step revenue recognition model to determine when and how revenue is recognized. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration it expects to receive in exchange for those goods or services. The standard also requires more detailed disclosures. The standard provides alternative methods of initial adoption and will be effective for us on January 1, 2017. Early adoption is not permitted. We are currently assessing the impact that this standard will have on our consolidated financial statements.

Restructuring_Charges_Tables

Restructuring Charges (Tables)	3 Months Ended
	Mar. 31, 2015
Restructuring Charges [Abstract]
Summary of Restructuring Charges
		Three Months Ended March 31, 2015
		(in millions)
	Rebranding of trade name	$	119
	Severance		18
	Facilities-related		3
	Asset impairments		9
	Other		1
	Total restructuring charges	$	150
Restructuring Reserve
		Balance at        January 1, 2015			Expense Incurred		Cash     Payments	Balance at         March 31, 2015
		(in millions)
	Severance	$	-	$	18	$	-1	$	17
	Facilities-related		-		3		-2		1
	Total	$	-	$	21	$	-3	$	18

Acquisitions_Tables

Acquisitions (Tables)	3 Months Ended
	Mar. 31, 2015
Acquisitions [Abstract]
Acquisition of Businesses
			Purchase Consideration			Total Net Assets (Liabilities) Acquired		Purchased Intangible Assets		Goodwill
			(in millions)
	Dorsey, Wright & Associates, LLC		$	226		$	-26	$	141	$	111
Purchased finite lived intangible assets acquired in the acquisition of DWA
					Estimated
					Average Remaining
		Value			Useful Life
	Intangible assets:		(in millions)		(in years)
	Trade name	$	108		Indefinite
	Customer relationships		29		15 years
	Technology		4		5 years
	Total intangible assets	$	141

Goodwill_and_Purchased_Intangi1

Goodwill and Purchased Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Goodwill and Purchased Intangible Assets [Abstract]
Schedule of Changes in Goodwill
			Market Services		Listing Services		Information Services		Technology Solutions		Total
			(in millions)
	Balance at December 31, 2014		$	3,081	$	114	$	1,794	$	549	$	5,538
	Goodwill acquired			-		-		111		-		111
	Foreign currency translation adjustment			-158		-11		-103		-27		-299
	Balance at March 31, 2015		$	2,923	$	103	$	1,802	$	522	$	5,350
Finite-Lived and Indefinite-Lived Intangible Assets
			31-Mar-15								31-Dec-14
			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		$	39	$	-18	$	21		5	$	35	$	-16	$	19		5
	Customer relationships			1,038		-343		695		20		1,009		-329		680		20
	Other			5		-3		2		9		5		-3		2		9
	Foreign currency translation adjustment			-138		39		-99				-94		26		-68
	Total finite-lived intangible assets		$	944	$	-325	$	619			$	955	$	-322	$	633
	Indefinite-Lived Intangible Assets
	Exchange and clearing registrations		$	790	$	-	$	790			$	790	$	-	$	790
	Trade names			745		-		745				756		-		756
	Licenses			51		-		51				51		-		51
	Foreign currency translation adjustment			-210		-		-210				-153		-		-153
	Total indefinite-lived intangible assets		$	1,376	$	-	$	1,376			$	1,444	$	-	$	1,444
	Total intangible assets		$	2,320	$	-325	$	1,995			$	2,399	$	-322	$	2,077
Estimated Future Amortization Expense			(in millions)
	2015(1)		$	50
	2016			66
	2017			64
	2018			61
	2019			47
	2020 and thereafter			430
	Total		$	718
		-1		Represents the estimated amortization to be recognized for the remaining nine months of 2015.

Deferred_Revenue_Tables

Deferred Revenue (Tables)	3 Months Ended
	Mar. 31, 2015
Deferred Revenue [Abstract]
Changes in Deferred Revenue			Initial Listing Revenues		Listing of Additional Shares Revenues		Annual Renewal and Other Revenues		Technology Solutions Revenues(2)		Total
			(in millions)
	Fiscal year ended:
	2015(1)		$	11	$	24	$	166	$	58	$	259
	2016			13		25		1		29		68
	2017			11		16		-		26		53
	2018			9		6		-		21		36
	2019			7		-		-		19		26
	2020 and thereafter			3		-		-		47		50
			$	54	$	71	$	167	$	200	$	492
		-1		Represents deferred revenue that is anticipated to be recognized over the remaining nine months of 2015.
		-2		The timing of recognition of our deferred Technology Solutions revenues is primarily dependent upon the completion of customization and any significant modifications made pursuant to existing Market Technology contracts and the timing of Corporate Solutions subscription-based contracts. As such, as it relates to Market Technology revenues, the timing represents our best estimate.
	The changes in our deferred revenue during the three months ended March 31, 2015 and 2014 are reflected in the following table.
			Initial Listing Revenues		Listing of Additional Shares Revenues		Annual Renewal and Other Revenues		Technology Solutions Revenues(2)		Total
			(in millions)
	Balance at January 1, 2015		$	54	$	78	$	13	$	247	$	392
	Additions(1)			4		3		218		161		386
	Amortization(1)			-4		-10		-63		-192		-269
	Translation adjustment			-		-		-1		-16		-17
	Balance at March 31, 2015		$	54	$	71	$	167	$	200	$	492
	Balance at January 1, 2014		$	41	$	75	$	20	$	158	$	294
	Additions(1)			5		10		181		225		421
	Amortization(1)			-3		-10		-58		-145		-216
	Translation adjustment			-		-		-		-1		-1
	Balance at March 31, 2014		$	43	$	75	$	143	$	237	$	498
		-1		The additions and amortization for initial listing revenues, listing of additional shares revenues and annual renewal and other revenues primarily reflect revenues from our U.S. Listing Services business. The additions to Technology Solutions revenues during the three months ended March 31, 2014 include $75 million related to the Borsa Istanbul market technology agreement.  See “Cost Method Investments,” of Note 6, “Investments,” for further discussion.
		-2		Technology Solutions deferred revenues primarily include revenues from our Market Technology delivered client contracts in the support phase charged during the period and our Corporate Solutions subscription based contracts, which are primarily billed quarterly in advance. For our Market Technology contracts, where customization and significant modifications to the software are made to meet the needs of our customers, total revenues, as well as costs incurred, are deferred until significant modifications are completed and delivered. Once delivered, deferred revenue and the related deferred costs are recognized over the post contract support period. For these Market Technology contracts, we have included the deferral of costs in other current assets and other non-current assets in the Condensed Consolidated Balance Sheets. The amortization of Technology Solutions deferred revenue primarily includes revenues earned from Market Technology client contracts and Corporate Solutions subscription based contracts recognized during the period.

Debt_Obligations_Tables

Debt Obligations (Tables)	3 Months Ended
	Mar. 31, 2015
Debt Obligations [Abstract]
Changes in Debt Obligations
			31-Dec-14		Additions		Payments, Conversions, Accretion and Other		31-Mar-15
			(in millions)
	5.55% senior unsecured notes due January 15, 2020 (net of discount)(1)		$	599	$	-	$	-	$	599
	5.25% senior unsecured notes due January 16, 2018 (net of discount)(1)			368		-		-		368
	3.875% senior unsecured notes due June 7, 2021 (net of discount)(1)			725		-		-82		643
	4.25% senior unsecured notes due June 1, 2024 (net of discount)(1)			498		-		-		498
	$750 million revolving credit commitment due November 25, 2019 (average interest rate of 1.50% for the period January 1, 2015 through March 31, 2015)(2)			123		100		-25		198
	Total long-term debt obligations		$	2,313	$	100	$	-107	$	2,306
		-1		See “Senior Unsecured Notes” below for further discussion.
		-2		See “2014 Credit Facility” below for further discussion.

Employee_Benefits_Tables

Employee Benefits (Tables)	3 Months Ended
	Mar. 31, 2015
Employee Benefits [Abstract]
Components of Net Periodic Benefit Cost
		Three Months Ended March 31,
		2015		2014
		(in millions)
	Components of net periodic benefit cost:
	Interest cost	$	1	$	2
	Expected return on plan assets		-1		-1
	Recognized net actuarial loss		1		-
	Net periodic benefit cost	$	1	$	1

ShareBased_Compensation_Tables

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2015
Share-Based Compensation [Abstract]
Schedule of Weighted-Average Assumptions Used to Determine the Weighted-Average Fair Values
			Three Months Ended March 31,
			2015			2014
	Weighted-average risk free interest rate			0.81%			0.79%
	Expected volatility(1)			21.5%			29.1%
	Grant date share price		$	50.94		$	36.94
	Annual dividend		$	0.60		$	0.60
	Weighted-average fair value at grant date		$	64.03		$	43.13
		-1		We use historic volatility for PSU awards issued under the TSR program, as implied volatility data could not be obtained for all the companies in the peer groups used for relative performance measurement within the TSR program.
Summary of Share-Based Compensation Expense
			Three Months Ended March 31,
			2015			2014
			(in millions)
	Share-based compensation expense before income taxes		$	14		$	14
	Income tax benefit			-6			-6
	Share-based compensation expense after income taxes		$	8		$	8
Summary of Stock Option Activity
			Number of Stock Options(1)			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term			Aggregate Intrinsic Value
								(in years)			(in millions)
	Outstanding at January 1, 2015			3,316,782		$	27.56		3.77		$	68
	Exercised			-232,459			25.78
	Outstanding at March 31, 2015			3,084,323		$	27.69		3.46		$	72
	Exercisable at March 31, 2015			3,084,323		$	27.69		3.46		$	72
		-1		No stock option awards were granted during the three months ended March 31, 2015.
Summary of Restricted Stock And PSU Activity
			Restricted Stock					PSUs
			Number of Awards			Weighted-Average Grant Date Fair Value		Number of Awards			Weighted-Average Grant Date Fair Value
	Unvested balances at January 1, 2015			3,193,230		$	30.99		2,212,607		$	32.69
	Granted			747,958	-1		49.22		841,966	-2		49.16
	Vested			-132,157			26.94		-837,109			22.50
	Forfeited			-71,543			32.37		-37,947			35.77
	Unvested balances at March 31, 2015			3,737,488		$	33.74		2,179,517		$	44.81
		-1		Primarily reflects our company-wide equity grant issued in March 2015, as discussed above.
		-2		PSUs granted in 2015 reflect awards issued to certain officers, as described above.

Nasdaq_Stockholders_Equity_Tab

Nasdaq Stockholders’ Equity (Tables)	3 Months Ended
	Mar. 31, 2015
Nasdaq Stockholders’ Equity [Abstract]
Schedule of Dividends Declared
	Declaration Date		Dividend Per		Record Date	Total Amount(1)		Payment Date
			Common Share
						(in millions)
	29-Jan-15		$	0.15	13-Mar-15	$	25	27-Mar-15
		-1		This amount was recorded in retained earnings in the Condensed Consolidated Balance Sheets at March 31, 2015.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Summary of Computation of Basic and Diluted Earnings Per Share
		Three Months Ended March 31,
		2015		2014
		(in millions, except share and per share amounts)
	Numerator:
	Net income attributable to common shareholders	$	9	$	103
	Denominator:
	Weighted-average common shares outstanding for basic earnings per share		168,985,956		169,595,951
	Weighted-average effect of dilutive securities:
	Employee equity awards		3,691,163		4,070,605
	Weighted-average common shares outstanding for diluted earnings per share		172,677,119		173,666,556
	Basic and diluted earnings per share:
	Basic earnings per share	$	0.05	$	0.61
	Diluted earnings per share	$	0.05	$	0.59

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value of Financial Instruments [Abstract]
Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis			31-Mar-15
			Total		Level 1		Level 2		Level 3
			(in millions)
	Financial Assets Measured at Fair Value on a Recurring Basis
	Financial investments, at fair value(1)		$	194	$	181	$	13	$	-
	Default fund and margin deposit investments(2)			2,494		692		1,802		-
	Total		$	2,688	$	873	$	1,815	$	-
			31-Dec-14
			Total		Level 1		Level 2		Level 3
			(in millions)
	Financial Assets Measured at Fair Value on a Recurring Basis
	Financial investments, at fair value(1)		$	174	$	171	$	3	$	-
	Default fund and margin deposit investments(2)			2,148		664		1,484		-
	Total		$	2,322	$	835	$	1,487	$	-
		-1		As of March 31, 2015 and December 31, 2014, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. Of these securities, $164 million as of March 31, 2015 and $159 million as of December 31, 2014 are assets utilized to meet regulatory capital requirements, primarily for the clearing operations of Nasdaq Nordic Clearing. As of March 31, 2015 and December 31, 2014, Level 2 financial investments, at fair value were primarily comprised of available-for-sale investment securities in short-term commercial paper.
		-2		Default fund and margin deposit investments include cash contributions invested by Nasdaq Nordic Clearing, in accordance with its investment policy, either in highly rated European, and to a lesser extent, U.S. government debt securities or reverse repurchase agreements with highly rated government debt securities as collateral. Of the total balance of $2,635 million recorded in the Condensed Consolidated Balance Sheets as of March 31, 2015, $692 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and $1,802 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance is held in cash. Of the total balance of $2,194 million recorded in the Condensed Consolidated Balance Sheets as of December 31, 2014, $664 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and term deposits and $1,484 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance was held in cash.

Clearing_Operations_Tables

Clearing Operations (Tables)	3 Months Ended
	Mar. 31, 2015
Clearing Operations [Abstract]
Schedule of Clearing Member Default Fund Contributions
			31-Mar-15
			Cash Contributions(1)		Non-Cash Contributions		Total Contributions
			(in millions)
	Default fund contributions		$	282	$	75	$	357
	Margin deposits			2,353		5,269		7,622
	Total		$	2,635	$	5,344	$	7,979
		-1		As of March 31, 2015, in accordance with its investment policy, Nasdaq Nordic Clearing has invested cash contributions of $1,802 million in reverse repurchase agreements and $692 million in highly rated European, and to a lesser extent, U.S. government debt securities. The remainder of this balance is held in cash.
Schedule of Derivative Contracts Outstanding	The market value of derivative contracts outstanding prior to netting was as follows:
			31-Mar-15
			(in millions)
	Commodity and seafood options, futures and forwards(1)(2)(3)		$	1,204
	Fixed-income options and futures(2)(3)			1,088
	Stock options and futures(2)(3)			178
	Index options and futures(2)(3)			222
	Total		$	2,692
		-1		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.
		-2		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.
		-3		We determined the fair value of our futures contracts based upon quoted market prices and average quoted market yields.
Schedule of Derivative Contracts Cleared	The total number of derivative contracts cleared through Nasdaq Nordic Clearing for the three months ended March 31, 2015 and 2014 was as follows:
			31-Mar-15		31-Mar-14
	Commodity and seafood options, futures and forwards(1)			620,417		634,742
	Fixed-income options and futures			4,449,856		5,761,558
	Stock options and futures			9,981,753		8,809,147
	Index options and futures			13,115,693		9,970,534
	Total			28,167,719		25,175,981
		-1		The total volume in cleared power related to commodity contracts was 363 Terawatt hours (TWh) for the three months ended March 31, 2015 and 429 TWh for the three months ended March 31, 2014.

Business_Segments_Tables

Business Segments (Tables)	3 Months Ended
	Mar. 31, 2015
Business Segments [Abstract]
Schedule of Operating Segments	The following table presents certain information regarding these operating segments for the three months ended March 31, 2015 and 2014.
			Market Services		Listing Services		Information Services		Technology Solutions		Corporate Items and Eliminations		Consolidated
			(in millions)
	Three Months Ended March 31, 2015
	Total revenues		$	539	$	64	$	125	$	130	$	-	$	858
	Transaction-based expenses			-351		-		-		-		-		-351
	Revenues less transaction-based expenses			188		64		125		130		-		507
	Operating income (loss)(1)		$	101	$	28	$	92	$	14	$	-208	$	27
	Three Months Ended March 31, 2014
	Total revenues		$	577	$	58	$	123	$	140	$	-	$	898
	Transaction-based expenses			-369		-		-		-		-		-369
	Revenues less transaction-based expenses			208		58		123		140		-		529
	Operating income (loss)(2)		$	105	$	22	$	92	$	13	$	-48	$	184
	(1)   Corporate items and eliminations for the three months ended March 31, 2015 include:
		·		restructuring charges of $150 million. See Note 3, “Restructuring Charges,” for further discussion;
		·		special legal expenses of $31 million;
		·		amortization expense of acquired intangible assets of $15 million; and
		·		reversal of VAT refund receivables no longer deemed collectible of $12 million.
	(2)   Corporate items and eliminations for the three months ended March 31, 2014 primarily include:
		·		merger and strategic initiatives expense of $28 million primarily related to the acquisition of the TR Corporate businesses and other strategic initiatives; and
		·		amortization expense of acquired intangible assets of $18 million.

Organization_and_Nature_of_Ope1

Organization and Nature of Operations (Details) (USD $)	3 Months Ended
	Mar. 31, 2015
	segment
Organization And Basis Of Presentation [Line Items]
Operations in number of continents	6
Number of Operating Segments	4
Market Services [Member] | Cash Equities Trading Markets [Member]
Organization And Basis Of Presentation [Line Items]
Number of exchanges	3
Market Services [Member] | Options Markets [Member]
Organization And Basis Of Presentation [Line Items]
Number of exchanges	3
Listing Services [Member]
Organization And Basis Of Presentation [Line Items]
Total number of U.S. listed companies	2,779
Approximate combined market capitalization, U.S.	8,200,000,000,000
Total number of listed companies within Nordic and Baltic exchanges	804
Approximate Combined Market Capitalization within Nordic and Baltic exchanges	1,300,000,000,000
Information Services [Member]
Organization And Basis Of Presentation [Line Items]
Number of indexes distributed and calculated	42,000
Assets management value	105,000,000,000
Technology Solutions [Member]
Organization And Basis Of Presentation [Line Items]
Number of clients	10,000
Number of exchanges	70
Services Provided Over Number Of Countries	50

Basis_of_Presentation_and_Prin2

Basis of Presentation and Principles of Consolidation (Details) (USD $)	3 Months Ended		48 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2012
Income Tax Examination [Line Items]
Tax Provision	$5	$53
Effective Income Tax Rate Continuing Operations	36.00%	34.00%
Finnish Tax Authority [Member] | FI
Income Tax Examination [Line Items]
Income Taxes Paid			35
Income Tax Examination, Penalties and Interest Expense			11
Tax expense (benefits) recorded	-24
Tax expense (benefits), per diluted share	($0.17)
Finnish Tax Authority [Member] | FI | Favorable outcome [Member]
Income Tax Examination [Line Items]
Tax expense (benefits) recorded	-30
Finnish Tax Authority [Member] | FI | Unfavorable outcome [Member]
Income Tax Examination [Line Items]
Tax expense (benefits) recorded	30
Swedish Supreme Administrative Court [Member] | SE
Income Tax Examination [Line Items]
Tax expense (benefits) recorded	-35
Tax expense (benefits), per diluted share	($0.20)
Swedish Tax Agency [Member] | SE
Income Tax Examination [Line Items]
Tax expense (benefits) recorded	12
Minimum [Member] | Swedish Supreme Administrative Court [Member] | SE
Income Tax Examination [Line Items]
Recurring quarterly tax benefits	3
Maximum [Member] | Swedish Supreme Administrative Court [Member] | SE
Income Tax Examination [Line Items]
Recurring quarterly tax benefits	$4

Restructuring_Charges_Narrativ

Restructuring Charges (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Restructuring Cost and Reserve [Line Items]
Estimated recognize pre-tax restructruing charges	$182
Restructuring and other charges	150	0
Pre-tax savings	17
Expected annualized savings	19
Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	18
Number of positions eliminated	199
Facilities-related [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	3
Asset impairments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	9
Rebranding of trade name [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$119

Restructuring_Charges_Summary_

Restructuring Charges (Summary of Restructuring Charges) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$150	$0
Rebranding of trade name [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	119
Severance [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	18
Facilities-related [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	3
Asset impairments [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	9
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$1

Restructuring_Charges_Restruct

Restructuring Charges (Restructuring Reserve) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Restructuring and Related Cost [Abstract]
Expenses Incurred	$21
Cash Payments	-3
Balance at March 31, 2015	18
Severance [Member]
Restructuring and Related Cost [Abstract]
Expenses Incurred	18
Cash Payments	-1
Balance at March 31, 2015	17
Facilities-related [Member]
Restructuring and Related Cost [Abstract]
Expenses Incurred	3
Cash Payments	-2
Balance at March 31, 2015	$1

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended	2 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Jan. 30, 2015	Mar. 31, 2015
Business Acquisition [Line Items]
Purchased intangible assets	141			$141
Customer relationships [Member]
Business Acquisition [Line Items]
Acquired Finite Lived Intangible Assets Weighted Average Useful Life	20 years	20 years
Estimated Average Remaining Useful Life	15 years
Technology [Member]
Business Acquisition [Line Items]
Acquired Finite Lived Intangible Assets Weighted Average Useful Life	5 years	5 years
Estimated Average Remaining Useful Life	5 years
Dorsey, Wright & Associates, LLC or DWA [Member]
Business Acquisition [Line Items]
Net assets acquired	-26			-26
Purchased intangible assets	141			141
Purchase consideration includes working capital adjustments			226
Business acquisition, cash paid			225
Net liabilities assumed			26
Acquisition recorded as non-current deferred tax liability			33
Business acquisition, working capital adjustments			1
Net assets Acquired			8
Deferred Tax Liabilites Current			1
DeferredTax Liabilities Noncurrent			33
Dorsey, Wright & Associates, LLC or DWA [Member] | Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Credit facility, proceeds				$100
Dorsey, Wright & Associates, LLC or DWA [Member] | Customer relationships [Member]
Business Acquisition [Line Items]
Estimated Average Remaining Useful Life	15 years
Dorsey, Wright & Associates, LLC or DWA [Member] | Customer relationships [Member] | Income Approach Valuation Technique [Member]
Business Acquisition [Line Items]
Premium rate	0.50%
Discount rate	17.50%
Discounted cash flows tax effect	36.50%
Amortization period of intangible assets for tax purposes	15 years
Customer relationships intangible assets, estimated percentage of revenues	100.00%
Dorsey, Wright & Associates, LLC or DWA [Member] | Technology [Member]
Business Acquisition [Line Items]
Acquired Finite Lived Intangible Assets Weighted Average Useful Life	5 years
Dorsey, Wright & Associates, LLC or DWA [Member] | Technology [Member] | Income Approach Valuation Technique [Member]
Business Acquisition [Line Items]
Discount rate	17.00%
Discounted cash flows tax effect	36.50%
Amortization period of intangible assets for tax purposes	15 years
Pre tax royalty rate	15.00%
Dorsey, Wright & Associates, LLC or DWA [Member] | Trade names [Member]
Business Acquisition [Line Items]
Amortization period of intangible assets for tax purposes	15 years
Dorsey, Wright & Associates, LLC or DWA [Member] | Trade names [Member] | Income Approach Valuation Technique [Member]
Business Acquisition [Line Items]
Discount rate	17.00%
Discounted cash flows tax effect	36.50%
Minimum [Member] | Dorsey, Wright & Associates, LLC or DWA [Member] | Customer relationships [Member] | Income Approach Valuation Technique [Member]
Business Acquisition [Line Items]
Customer relationships intangible assets, period of growth	3 years
Minimum [Member] | Dorsey, Wright & Associates, LLC or DWA [Member] | Technology [Member]
Business Acquisition [Line Items]
Royalty rate, profit split	25.00%
Maximum [Member] | Dorsey, Wright & Associates, LLC or DWA [Member] | Customer relationships [Member] | Income Approach Valuation Technique [Member]
Business Acquisition [Line Items]
Customer relationships intangible assets, period of growth	6 years
Maximum [Member] | Dorsey, Wright & Associates, LLC or DWA [Member] | Technology [Member]
Business Acquisition [Line Items]
Royalty rate, profit split	30.00%

Acquisitions_Acquisition_of_Bu

Acquisitions (Acquisition of Businesses) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Business Acquisition [Line Items]
Purchased intangible assets	$141
Goodwill	5,350	5,538
Dorsey, Wright & Associates, LLC or DWA [Member]
Business Acquisition [Line Items]
Purchase consideration	226
Net assets acquired	-26
Purchased intangible assets	141
Goodwill	$111

Acquisitions_Purchased_finite_

Acquisitions (Purchased finite lived intangible assets acquired in the acquisition of DWA) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Purchased intangible assets	$141
Trade names [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets Acquired	108
Technology [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Estimated Average Remaining Useful Life	5 years
Finite-lived Intangible Assets Acquired	4
Customer relationships [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Estimated Average Remaining Useful Life	15 years
Finite-lived Intangible Assets Acquired	$29

Goodwill_and_Purchased_Intangi2

Goodwill and Purchased Intangible Assets (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill expected to be deductible in future periods	$898,000,000
Amortization expense for purchased finite-lived intangible assets	15,000,000	18,000,000
Goodwill Impairment Loss	0	0
Rebranding of trade name [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Non-cash intangible asset impairment charges	119,000,000
eSpeed [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill expected to be deductible in future periods	525,000,000
TR Corporate Solutions Businesses [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill expected to be deductible in future periods	273,000,000
Dorsey, Wright & Associates, LLC or DWA [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill expected to be deductible in future periods	$38,000,000

Goodwill_and_Purchased_Intangi3

Goodwill and Purchased Intangible Assets (Schedule of Changes in Goodwill) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Goodwill [Line Items]
Balance	$5,538
Goodwill acquired	111
Foreign currency translation adjustment	-299
Balance	5,350
Market Services [Member]
Goodwill [Line Items]
Balance	3,081
Foreign currency translation adjustment	-158
Balance	2,923
Listing Services [Member]
Goodwill [Line Items]
Balance	114
Foreign currency translation adjustment	-11
Balance	103
Information Services [Member]
Goodwill [Line Items]
Balance	1,794
Goodwill acquired	111
Foreign currency translation adjustment	-103
Balance	1,802
Technology Solutions [Member]
Goodwill [Line Items]
Balance	549
Foreign currency translation adjustment	-27
Balance	$522

Goodwill_and_Purchased_Intangi4

Goodwill and Purchased Intangible Assets (Finite-Lived and Indefinite-Lived Intangible Assets) (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total Finite-Lived Intangible Assets, Gross Amount	$944	$955
Accumulated Amortization	-325	-322
Total	619	633
Total indefinite-lived intangible assets, Net Amount	1,376	1,444
Total Intangible Assets, Gross Amount	2,320	2,399
Total Intangible Assets, Net Amount	1,995	2,077
Exchange and clearing registrations [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Net Amount	790	790
Trade names [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Net Amount	745	756
Licenses [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Net Amount	51	51
Foreign currency translation adjustment [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total indefinite-lived intangible assets, Net Amount	-210	-153
Technology [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total Finite-Lived Intangible Assets, Gross Amount	39	35
Accumulated Amortization	-18	-16
Total	21	19
Total finite-lived intangible assets, Weighted-Average Useful Life (in Years)	5 years	5 years
Customer relationships [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total Finite-Lived Intangible Assets, Gross Amount	1,038	1,009
Accumulated Amortization	-343	-329
Total	695	680
Total finite-lived intangible assets, Weighted-Average Useful Life (in Years)	20 years	20 years
Other [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total Finite-Lived Intangible Assets, Gross Amount	5	5
Accumulated Amortization	-3	-3
Total	2	2
Total finite-lived intangible assets, Weighted-Average Useful Life (in Years)	9 years	9 years
Foreign currency translation adjustment [Member]
Finite Lived And Indefinite Lived Intangible Assets [Line Items]
Total Finite-Lived Intangible Assets, Gross Amount	-138	-94
Accumulated Amortization	39	26
Total	($99)	($68)

Goodwill_and_Purchased_Intangi5

Goodwill and Purchased Intangible Assets (Estimated Future Amortization Expense) (Details) (USD $)	Mar. 31, 2015
In Millions, unless otherwise specified
Goodwill and Purchased Intangible Assets [Abstract]
2015	$50	[1]
2016	66
2017	64
2018	61
2019	47
2020 and thereafter	430
Total	$718
[1]	Represents the estimated amortization to be recognized for the remaining nine months of 2015.

Investments_Details

Investments (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Investments, Debt and Securities [Line Items]
Trading securities	$181	$171
Equity method investments	67	25
Net income from unconsolidated investees	14
Carrying cost of Investment	132	138
Borsa Istanbul Cost Method Investment[Member]
Investments, Debt and Securities [Line Items]
Carrying cost of Investment			75
Cost Method Investment Ownership Percentage	5.00%	5.00%
LCH [Member]
Investments, Debt and Securities [Line Items]
Cost Method Investment Ownership Percentage	5.00%	5.00%
Foreign Government Debt Securities [Member]
Investments, Debt and Securities [Line Items]
Trading securities	164	159
OCC [Member]
Investments, Debt and Securities [Line Items]
Payments to Acquire Equity Method Investments	30
Contribution In Equity Capital	150
Annual dividend From Shareholders percentage	50.00%
OCC [Member] | Other Income [Member]
Investments, Debt and Securities [Line Items]
Net income from unconsolidated investees		$13

Deferred_Revenue_Estimated_Def

Deferred Revenue (Estimated Deferred Revenue) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014		Mar. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Deferred Revenue Arrangement [Line Items]
2015	$259	[1]
2016	68
2017	53
2018	36
2019	26
2020 and thereafter	50
Deferred revenue estimated revenue to be recognized	492		392		498		294
Initial Listing Revenues [Member]
Deferred Revenue Arrangement [Line Items]
2015	11	[1]
2016	13
2017	11
2018	9
2019	7
2020 and thereafter	3
Deferred revenue estimated revenue to be recognized	54		54		43		41
Listing of Additional Shares Revenues [Member]
Deferred Revenue Arrangement [Line Items]
2015	24	[1]
2016	25
2017	16
2018	6
Deferred revenue estimated revenue to be recognized	71		78		75		75
Annual Renewal and Other Revenues [Member]
Deferred Revenue Arrangement [Line Items]
2015	166	[1]
2016	1
Deferred revenue estimated revenue to be recognized	167		13		143		20
Technology Solutions [Member]
Deferred Revenue Arrangement [Line Items]
2015	58	[1],[2]
2016	29	[2]
2017	26	[2]
2018	21	[2]
2019	19	[2]
2020 and thereafter	47	[2]
Deferred revenue estimated revenue to be recognized	$200	[2],[3]	$247	[3]	$237	[3]	$158	[3]
[1]	Represents deferred revenue that is anticipated to be recognized over the remaining nine months of 2015.
[2]	The timing of recognition of our deferred Technology Solutions revenues is primarily dependent upon the completion of customization and any significant modifications made pursuant to existing Market Technology contracts and the timing of Corporate Solutions subscription-based contracts. As such, as it relates to Market Technology revenues, the timing represents our best estimate.
[3]	Technology Solutions deferred revenues primarily include revenues from our Market Technology delivered client contracts in the support phase charged during the period and our Corporate Solutions subscription based contracts, which are primarily billed quarterly in advance. For our Market Technology contracts, where customization and significant modifications to the software are made to meet the needs of our customers, total revenues, as well as costs incurred, are deferred until significant modifications are completed and delivered. Once delivered, deferred revenue and the related deferred costs are recognized over the post contract support period. For these Market Technology contracts, we have included the deferral of costs in other current assets and other non-current assets in the Condensed Consolidated Balance Sheets. The amortization of Technology Solutions deferred revenue primarily includes revenues earned from Market Technology client contracts and Corporate Solutions subscription based contracts recognized during the period.

Deferred_Revenue_Changes_in_De

Deferred Revenue (Changes in Deferred Revenue) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Deferred Revenue Arrangement [Line Items]
Balance	$392		$294
Additions	386	[1]	421	[1]
Amortization	-269	[1]	-216	[1]
Translation adjustment	-17		-1
Balance	492		498
Initial Listing Revenues [Member]
Deferred Revenue Arrangement [Line Items]
Balance	54		41
Additions	4	[1]	5	[1]
Amortization	-4	[1]	-3	[1]
Balance	54		43
Listing of Additional Shares Revenues [Member]
Deferred Revenue Arrangement [Line Items]
Balance	78		75
Additions	3	[1]	10	[1]
Amortization	-10	[1]	-10	[1]
Balance	71		75
Annual Renewal and Other Revenues [Member]
Deferred Revenue Arrangement [Line Items]
Balance	13		20
Additions	218	[1]	181	[1]
Amortization	-63	[1]	-58	[1]
Translation adjustment	-1
Balance	167		143
Technology Solutions [Member]
Deferred Revenue Arrangement [Line Items]
Balance	247	[2]	158	[2]
Additions	161	[1],[2]	225	[1],[2]
Amortization	-192	[1],[2]	-145	[1],[2]
Translation adjustment	-16	[2]	-1	[2]
Balance	200	[2],[3]	237	[2]
Borsa Istanbul Cost Method Investment[Member]
Deferred Revenue Arrangement [Line Items]
Additions			$75
[1]	The additions and amortization for initial listing revenues, listing of additional shares revenues and annual renewal and other revenues primarily reflect revenues from our U.S. Listing Services business. The additions to Technology Solutions revenues during the three months ended March 31, 2014 include $75 million related to the Borsa Istanbul market technology agreement. See “Cost Method Investments,” of Note 6, “Investments,” for further discussion.
[2]	Technology Solutions deferred revenues primarily include revenues from our Market Technology delivered client contracts in the support phase charged during the period and our Corporate Solutions subscription based contracts, which are primarily billed quarterly in advance. For our Market Technology contracts, where customization and significant modifications to the software are made to meet the needs of our customers, total revenues, as well as costs incurred, are deferred until significant modifications are completed and delivered. Once delivered, deferred revenue and the related deferred costs are recognized over the post contract support period. For these Market Technology contracts, we have included the deferral of costs in other current assets and other non-current assets in the Condensed Consolidated Balance Sheets. The amortization of Technology Solutions deferred revenue primarily includes revenues earned from Market Technology client contracts and Corporate Solutions subscription based contracts recognized during the period.
[3]	The timing of recognition of our deferred Technology Solutions revenues is primarily dependent upon the completion of customization and any significant modifications made pursuant to existing Market Technology contracts and the timing of Corporate Solutions subscription-based contracts. As such, as it relates to Market Technology revenues, the timing represents our best estimate.

Debt_Obligations_555_Senior_Un

Debt Obligations (5.55% Senior Unsecured Notes) (Details) (5.55% senior unsecured notes due January 15, 2020 [Member], USD $)	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
5.55% senior unsecured notes due January 15, 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$600,000,000
Debt instrument, interest rate	5.55%
Debt instrument, maturity date	15-Jan-20
Deferred finance charge	5,000,000
Total debt obligations	$599,000,000	[1]	$599,000,000	[1]
[1]	See “Senior Unsecured Notes” below for further discussion.

Debt_Obligations_525_Senior_Un

Debt Obligations (5.25% Senior Unsecured Notes) (Details) (5.25% senior unsecured notes due January 16, 2018 [Member], USD $)	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
5.25% senior unsecured notes due January 16, 2018 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$370,000,000
Debt instrument, interest rate	5.25%
Debt instrument, maturity date	16-Jan-18
Deferred Finance Costs Gross	3,000,000
Debt instrument, interest rate, maximum	7.25%
Total debt obligations	$368,000,000	[1]	$368,000,000	[1]
Aggregate principal amount purchased plus accrued and unpaid interest	101.00%
[1]	See “Senior Unsecured Notes” below for further discussion.

Debt_Obligations_3875_Senior_U

Debt Obligations (3.875% Senior Unsecured Notes) (Details)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015		Mar. 31, 2015	Dec. 31, 2014
	USD ($)	USD ($)	3.875% senior unsecured notes due June 7, 2021 [Member]		3.875% senior unsecured notes due June 7, 2021 [Member]	3.875% senior unsecured notes due June 7, 2021 [Member]
			USD ($)		EUR (€)	USD ($)
Debt Instrument [Line Items]
Total debt obligations			$643	[1]		$725	[1]
Debt Instrument Carrying Amount					600
Debt instrument, interest rate			3.88%
Debt instrument, maturity date			7-Jun-21
Deferred Finance Costs Gross			7
Debt instrument, interest rate, maximum			5.88%
Aggregate principal amount purchased plus accrued and unpaid interest			101.00%
Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax	($314)	($12)	$82
[1]	See “Senior Unsecured Notes” below for further discussion.

Debt_Obligations_425_Senior_Un

Debt Obligations (4.25% Senior Unsecured Notes) (Details) (4.25% Senior Unsecured Notes Due June 1 2024 [Member], USD $)	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
4.25% Senior Unsecured Notes Due June 1 2024 [Member]
Debt Instrument [Line Items]
Total debt obligations	$498,000,000	[1]	$498,000,000	[1]
Debt Instrument Face Amount	500,000,000
Deferred Finance Costs Gross	$4,000,000
Debt instrument, interest rate	4.25%
Debt instrument, maturity date	1-Jun-24
Debt instrument, interest rate, maximum	6.25%
Aggregate principal amount purchased plus accrued and unpaid interest	101.00%
[1]	See “Senior Unsecured Notes” below for further discussion.

Debt_Obligations_2014_Credit_F

Debt Obligations (2014 Credit Facility) (Details) (Revolving Credit Facility [Member], USD $)	2 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2015
Dorsey, Wright & Associates, LLC or DWA [Member]
Debt Instrument [Line Items]
Credit facility, proceeds	$100
$750 million revolving credit commitment due November 25, 2019 [Member]
Debt Instrument [Line Items]
Credit facility, borrowing capacity	750	750
Line Of Credit Facility Maximum Borrowing Capacity	750	750
Deferred Finance Costs Gross	3	3
Repayments of Long-term Lines of Credit		25
$750 million revolving credit commitment due November 25, 2019 [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Additional Capacity Option	$500	$500

Debt_Obligations_Other_Credit_

Debt Obligations (Other Credit Facilities) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Debt Instrument [Line Items]
Line of credit, outstanding amount		$7
Clearinghouse Credit Facilities [Member]
Debt Instrument [Line Items]
Credit facility, borrowing capacity	179	236
Line of credit facility, available liquidity	179	197
Credit facility satisfy regulatory requirements		39
Line of credit, outstanding amount	$0	$7

Debt_Obligations_Changes_in_De

Debt Obligations (Changes in Debt Obligations) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Debt Instrument [Line Items]
Total long-term debt obligations	$2,306	[1]	$2,313	[1]
Additions	100	[1]
Payments, Conversions, Accretion and Other	-107	[1]
5.55% senior unsecured notes due January 15, 2020 [Member]
Debt Instrument [Line Items]
Total debt obligations	599	[2]	599	[2]
5.25% senior unsecured notes due January 16, 2018 [Member]
Debt Instrument [Line Items]
Total debt obligations	368	[2]	368	[2]
3.875% senior unsecured notes due June 7, 2021 [Member]
Debt Instrument [Line Items]
Total debt obligations	643	[2]	725	[2]
Payments, Conversions, Accretion and Other	-82	[2]
4.25% Senior Unsecured Notes Due June 1 2024 [Member]
Debt Instrument [Line Items]
Total debt obligations	498	[2]	498	[2]
$750 million revolving credit commitment due November 25, 2019 [Member]
Debt Instrument [Line Items]
Total debt obligations	198	[1],[2]	123	[1],[2]
Additions	100	[1],[2]
Payments, Conversions, Accretion and Other	($25)	[1],[2]
Revolving Credit Facility [Member] | $750 million revolving credit commitment due November 25, 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate During Period	1.50%
[1]	See “2014 Credit Facility” below for further discussion.
[2]	See “Senior Unsecured Notes” below for further discussion.

Debt_Obligations_Changes_in_De1

Debt Obligations (Changes in Debt Obligations Additional Information) (Details)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2015	Mar. 31, 2015	Mar. 31, 2015	Mar. 31, 2015
	5.55% senior unsecured notes due January 15, 2020 [Member]	5.25% senior unsecured notes due January 16, 2018 [Member]	3.875% senior unsecured notes due June 7, 2021 [Member]	4.25% Senior Unsecured Notes Due June 1 2024 [Member]	Revolving Credit Facility [Member]
			EUR (€)		$750 million revolving credit commitment due November 25, 2019 [Member]
					USD ($)
Debt Instrument [Line Items]
Debt instrument, interest rate	5.55%	5.25%	3.88%	4.25%
Debt instrument, maturity date	15-Jan-20	16-Jan-18	7-Jun-21	1-Jun-24	25-Nov-19
Debt instrument, principal outstanding			€ 600
Credit facility, borrowing capacity					$750

Employee_Benefits_Narrative_De

Employee Benefits (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Benefit cost	$1	$1
Common stock shares reserved for future issuance	6.5
Compensation expenses	1	1
Savings Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contributions plan expense	3	2
Non-U.S. Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Cost or expenses included in compensation and benefit expense	$5	$5
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of employer contributions	100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	100.00%
Percentage of eligible employee contributions receiving employer contributions	6.00%
Share-based compensation [Member]
Defined Benefit Plan Disclosure [Line Items]
Common stock shares reserved for future issuance	2.8
Offering periods for ESPP shares, months	6 months
Percentage of fair market value of common stock	85.00%
Percentage of discount to employees on purchase of common stock under ESPP	15.00%

Employee_Benefits_Components_o

Employee Benefits (Components of Net Periodic Benefit Cost) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Employee Benefits [Abstract]
Interest cost	$1	$2
Expected return on plan assets	-1	-1
Recognized net actuarial loss	1
Net periodic benefit cost	$1	$1

ShareBased_Compensation_Narrat

Share-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares reserved for future issuance	6,500,000
Discount from market price	15.00%
Net cash proceeds from the exercise of stock options	$6		$7
Stock options exercised in period	232,459	[1]	367,115
Stock options, exercisable	3,084,323	[1]
Weighted-average exercise price	$27.69		$25.72
Total fair value of stock option vested			11
Total pre-tax intrinsic value of stock options exercised	5		7
Stock options, granted	0
Stock options to purchase shares	3,084,323	[1]		3,316,782	[1]
Closing stock price	$50.94		$36.94
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Number of Awards, Granted	841,966	[2]
Number of peer groups	2
Performance-based long-term incentive program weighted percentage	50.00%
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period 1	3 years
PSUs [Member] | Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards, Granted	595,732		416,380
Chief executive officer's and executive vice presidents' long-term stock-based compensation	100.00%
Share Based Compensation Arrangement By Share Based Payment Award Percentage of maximum shares earned for a negative three-year performanace period	100.00%
PSUs [Member] | Senior vice presidents' [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Chief executive officer's and executive vice presidents' long-term stock-based compensation	50.00%
Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards, Granted	747,958	[3]
General expiration period of stock options	10 years
Restricted stock [Member] | Fourth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Restricted stock [Member] | Second Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
Restricted stock [Member] | Third Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
One-year performance period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional PSU's Granted	21,429
One-year performance period [Member] | Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards, Granted	179,352
Three-year performance period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional PSU's Granted	224,805
Restricted stock and PSU's [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost	$132
Weighted-average period unrecognized compensation cost is expected to be recognized, in years	1 year 9 months 18 days
Common stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options to purchase shares	3,084,323		4,532,006
Minimum [Member] | PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Minimum [Member] | PSUs [Member] | Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Minimum [Member] | Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period 1	2 years
Maximum [Member] | PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%
Maximum [Member] | PSUs [Member] | Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	200.00%
Maximum [Member] | Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period 1	5 years
[1]	No stock option awards were granted during the three months ended March 31, 2015.
[2]	PSUs granted in 2015 reflect awards issued to certain officers, as described above.
[3]	Primarily reflects our company-wide equity grant issued in March 2015, as discussed above.

Sharedbased_Compensation_Sched

Shared-based Compensation (Schedule of Weighted- Average Assumptions Used to Determine Weighted-Average Fair Values) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Weighted-average risk free interest rate	0.81%		0.79%
Expected volatility	21.50%	[1]	29.10%	[1]
Grant date share price	$50.94		$36.94
Annual dividend	$0.60		$0.60
Weighted-average fair value at grant date	$64.03		$43.13
[1]	We use historic volatility for PSU awards issued under the TSR program, as implied volatility data could not be obtained for all the companies in the peer groups used for relative performance measurement within the TSR program.

ShareBased_Compensation_Summar

Share-Based Compensation (Summary of Share-Based Compensation Expense) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Share-Based Compensation [Abstract]
Share-based compensation expense before income taxes	$14	$14
Income tax benefit	-6	-6
Share-based compensation expense after income taxes	$8	$8

ShareBased_Compensation_Summar1

Share-Based Compensation (Summary of Stock Option Activity) (Details) (USD $)	3 Months Ended			12 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Share-Based Compensation [Abstract]
Number of Stock Options Outstanding, Beginning of period	3,316,782	[1]
Stock options amortization and exercises, net (in shares)	-232,459	[1]	-367,115
Number of Stock Options Outstanding, End of period	3,084,323	[1]		3,316,782	[1]
Stock options, exercisable	3,084,323	[1]
Weighted-Average Exercise Price, Outstanding Beginning of period	$27.56
Weighted-Average Exercise Price, Exercised	$25.78
Weighted-Average Exercise Price, Outstanding End of period	$27.69			$27.56
Weighted-average exercise price	$27.69		$25.72
Options Outstanding, Weighted-Average Remaining Contractual Term, outstanding (in years)	3 years 5 months 16 days			3 years 9 months 7 days
Aggregate Intrinsic Value, Options Outstanding	$72			$68
Options Outstanding, Weighted-Average Remaining Contractual Term, exercisable (in years)	3 years 5 months 16 days
Aggregate Intrinsic Value, Exercisable	$72
Stock options, granted	0
[1]	No stock option awards were granted during the three months ended March 31, 2015.

ShareBased_Compensation_Summar2

Share-Based Compensation (Summary of Restricted Stock and PSU Activity) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015
Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards, Unvested balances	3,193,230
Number of Awards, Granted	747,958	[1]
Number of Awards, Vested	-132,157
Number of Awards, Forfeited	-71,543
Number of Awards, Unvested balances	3,737,488
Weighted-Average Grant Date Fair Value, Unvested balances	$30.99
Weighted-Average Grant Date Fair Value, Granted	$49.22
Weighted-Average Grant Date Fair Value, Vested	$26.94
Weighted-Average Grant Date Fair Value, Forfeited	$32.37
Weighted-Average Grant Date Fair Value, Unvested balances	$33.74
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards, Unvested balances	2,212,607
Number of Awards, Granted	841,966	[2]
Number of Awards, Vested	-837,109
Number of Awards, Forfeited	-37,947
Number of Awards, Unvested balances	2,179,517
Weighted-Average Grant Date Fair Value, Unvested balances	$32.69
Weighted-Average Grant Date Fair Value, Granted	$49.16
Weighted-Average Grant Date Fair Value, Vested	$22.50
Weighted-Average Grant Date Fair Value, Forfeited	$35.77
Weighted-Average Grant Date Fair Value, Unvested balances	$44.81
[1]	Primarily reflects our company-wide equity grant issued in March 2015, as discussed above.
[2]	PSUs granted in 2015 reflect awards issued to certain officers, as described above.

Nasdaq_Stockholders_Equity_Nar

Nasdaq Stockholders' Equity (Narrative) (Details) (USD $)	3 Months Ended		1 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Apr. 30, 2015	Dec. 31, 2014	Sep. 30, 2012
Stockholders Equity [Line Items]
Common stock, shares authorized	300,000,000			300,000,000
Common stock, shares issued	171,527,299			170,325,304
Common stock, shares outstanding	168,927,790			168,795,263
Common stock holder voting rights, maximum percentage of the then-outstanding shares of Nasdaq common stock	5.00%
Common stock in treasury, shares	2,599,509			1,530,041
Share repurchase program, authorized amount				$500	$300
Remaining authorized share repurchase amounts under repurchase program	507
Treasury shares acquired	599,951
Average per share price of repurchased stock	$50.08
Aggregate purchase price	$30
Cash dividend per share	$0.15	$0.28
Other Repurchases of Common Stock [Member]
Stockholders Equity [Line Items]
Treasury shares acquired	469,517
Subsequent Event [Member]
Stockholders Equity [Line Items]
Cash dividend per share			$0.25
Dividend declared, date payable	26-Jun-15
Dividend declared, record date	12-Jun-15
Increase from prior quarter cash dividend, percentage			67.00%

Nasdaq_Stockholders_Equity_Sch

Nasdaq Stockholders' Equity (Schedule of Dividends Declared) (Details) (USD $)	3 Months Ended			0 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014	Jan. 29, 2015
Dividends Payable [Line Items]
Dividend Per Common Share	$0.15		$0.28
January 30, 2014 [Member]
Dividends Payable [Line Items]
Declaration Date	29-Jan-15
Dividend Per Common Share				$0.15
Record Date	13-Mar-15
Total Amount	$25	[1]
Payment Date	27-Mar-15
[1]	This amount was recorded in retained earnings in the Condensed Consolidated Balance Sheets at March 31, 2015.

Earnings_Per_Share_Narrative_D

Earnings Per Share (Narrative) (Details)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Stock options to purchase shares	3,084,323	[1]		3,316,782	[1]
Diluted shares outstanding	3,691,163		4,070,605
Common stock [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Stock options to purchase shares	3,084,323		4,532,006
Restricted stock and PSU's [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Restricted stock and PSU's outstanding	5,917,005		5,938,944
Diluted shares outstanding	4,573,314		4,262,190
Employee Stock Option [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Diluted shares outstanding			4,398,297
[1]	No stock option awards were granted during the three months ended March 31, 2015.

Earnings_Per_Share_Summary_of_

Earnings Per Share (Summary of Computation of Basic and Diluted Earnings Per Share) (Details) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Net income attributable to common shareholders	$9	$103
Weighted-average common shares outstanding for basic earnings per share	168,985,956	169,595,951
Employee equity awards	3,691,163	4,070,605
Weighted-average common shares outstanding for diluted earnings per share	172,677,119	173,666,556
Basic earnings per share	$0.05	$0.61
Diluted earnings per share	$0.05	$0.59

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments (Narrative) (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014
In Billions, unless otherwise specified
Fair Value of Financial Instruments [Abstract]
Fair value of debt utilizing discounted cash flow analyses	$2.50	$2.50

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial investments, at fair value	$194	[1]	$174	[1]
Default fund and margin deposit investments	2,494	[2]	2,148	[2]
Total	2,688		2,322
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial investments, at fair value	181	[1]	171	[1]
Default fund and margin deposit investments	692	[2]	664	[2]
Total	873		835
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial investments, at fair value	13	[1]	3	[1]
Default fund and margin deposit investments	1,802	[2]	1,484	[2]
Total	$1,815		$1,487
[1]	As of March 31, 2015 and December 31, 2014, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. Of these securities, $164 million as of March 31, 2015 and $159 million as of December 31, 2014 are assets utilized to meet regulatory capital requirements, primarily for the clearing operations of Nasdaq Nordic Clearing. As of March 31, 2015 and December 31, 2014, Level 2 financial investments, at fair value were primarily comprised of available-for-sale investment securities in short-term commercial paper.
[2]	Default fund and margin deposit investments include cash contributions invested by Nasdaq Nordic Clearing, in accordance with its investment policy, either in highly rated European, and to a lesser extent, U.S. government debt securities or reverse repurchase agreements with highly rated government debt securities as collateral. Of the total balance of $2,635 million recorded in the Condensed Consolidated Balance Sheets as of March 31, 2015, $692 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and $1,802 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance is held in cash. Of the total balance of $2,194 million recorded in the Condensed Consolidated Balance Sheets as of December 31, 2014, $664 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and term deposits and $1,484 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance was held in cash.

Fair_Value_of_Financial_Instru4

Fair Value of Financial Instruments (Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Additional Information) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial investments, at fair value	$174	[1]	$194	[1]
Default funds and margin deposits	2,194		2,635
Default fund and margin deposit investments	2,148	[2]	2,494	[2]
Restricted assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial investments, at fair value	159		164
Reverse Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Default funds and margin deposits	1,484
Default fund and margin deposit investments			1,802
US Government Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Highly Rated Government Debt Securities	664
Default fund and margin deposit investments			$692
[1]	As of March 31, 2015 and December 31, 2014, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. Of these securities, $164 million as of March 31, 2015 and $159 million as of December 31, 2014 are assets utilized to meet regulatory capital requirements, primarily for the clearing operations of Nasdaq Nordic Clearing. As of March 31, 2015 and December 31, 2014, Level 2 financial investments, at fair value were primarily comprised of available-for-sale investment securities in short-term commercial paper.
[2]	Default fund and margin deposit investments include cash contributions invested by Nasdaq Nordic Clearing, in accordance with its investment policy, either in highly rated European, and to a lesser extent, U.S. government debt securities or reverse repurchase agreements with highly rated government debt securities as collateral. Of the total balance of $2,635 million recorded in the Condensed Consolidated Balance Sheets as of March 31, 2015, $692 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and $1,802 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance is held in cash. Of the total balance of $2,194 million recorded in the Condensed Consolidated Balance Sheets as of December 31, 2014, $664 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and term deposits and $1,484 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance was held in cash.

Clearing_Operations_Narrative_

Clearing Operations (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014	Dec. 31, 2014
	contract		contract
Clearing Operations [Line Items]
Marketable Securities Current	$194,000,000	[1]		$174,000,000	[1]
Default fund and margin deposit investments	2,494,000,000	[2]		2,148,000,000	[2]
Reverse Repurchase Agreements [Member]
Clearing Operations [Line Items]
Default fund and margin deposit investments	1,802,000,000
US Government Debt Securities [Member]
Clearing Operations [Line Items]
Default fund and margin deposit investments	692,000,000
NASDAQ Nordic Clearing [Member]
Clearing Operations [Line Items]
Contract value of resale and repurchase agreements	3,600,000,000		3,900,000,000
Total number of derivative contracts cleared	1,582,082		1,209,945
Power of assessment of the clearing member's contribution to the financial markets and commodities markets default funds	100.00%
Marketable Securities Current	126,000,000
Liability Waterfall [Member]
Clearing Operations [Line Items]
Junior capital, cash deposits and pledged assets	18,000,000
Senior capital, cash deposits and pledged assets	$35,000,000
[1]	As of March 31, 2015 and December 31, 2014, Level 1 financial investments, at fair value were primarily comprised of trading securities, mainly highly rated European government debt securities. Of these securities, $164 million as of March 31, 2015 and $159 million as of December 31, 2014 are assets utilized to meet regulatory capital requirements, primarily for the clearing operations of Nasdaq Nordic Clearing. As of March 31, 2015 and December 31, 2014, Level 2 financial investments, at fair value were primarily comprised of available-for-sale investment securities in short-term commercial paper.
[2]	Default fund and margin deposit investments include cash contributions invested by Nasdaq Nordic Clearing, in accordance with its investment policy, either in highly rated European, and to a lesser extent, U.S. government debt securities or reverse repurchase agreements with highly rated government debt securities as collateral. Of the total balance of $2,635 million recorded in the Condensed Consolidated Balance Sheets as of March 31, 2015, $692 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and $1,802 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance is held in cash. Of the total balance of $2,194 million recorded in the Condensed Consolidated Balance Sheets as of December 31, 2014, $664 million of cash contributions have been invested in highly rated European, and to a lesser extent, U.S. government debt securities and term deposits and $1,484 million of cash contributions have been invested in reverse repurchase agreements. The remainder of this balance was held in cash.

Clearing_Operations_Schedule_o

Clearing Operations (Schedule of Clearing Member Default Fund Contributions And Margin Deposits) (Details) (USD $)	Mar. 31, 2015
In Millions, unless otherwise specified
Clearing Operations [Line Items]
Default fund contributions	$357
Margin deposits	7,622
Default fund contributions and margin deposits	7,979
Cash Contributions [Member]
Clearing Operations [Line Items]
Default fund contributions	282	[1]
Margin deposits	2,353	[1]
Default fund contributions and margin deposits	2,635	[1]
Non-Cash Contributions [Member]
Clearing Operations [Line Items]
Default fund contributions	75
Margin deposits	5,269
Default fund contributions and margin deposits	$5,344
[1]	As of March 31, 2015, in accordance with its investment policy, Nasdaq Nordic Clearing has invested cash contributions of $1,802 million in reverse repurchase agreements and $692 million in highly rated European, and to a lesser extent, U.S. government debt securities

Clearing_Operations_Schedule_o1

Clearing Operations (Schedule of Derivative Contracts Outstanding) (Details) (USD $)	Mar. 31, 2015		Mar. 31, 2014
In Millions, unless otherwise specified	contract		contract
Clearing Operations [Line Items]
Market value of derivative contracts	$2,692	[1],[2]
Total Number of Cleared Contracts	28,167,719		25,175,981
Commodity forwards and options [Member]
Clearing Operations [Line Items]
Market value of derivative contracts	1,204	[1],[2],[3]
Total Number of Cleared Contracts	620,417	[4]	634,742	[4]
Fixed-income options and futures [Member]
Clearing Operations [Line Items]
Market value of derivative contracts	1,088	[1],[2]
Total Number of Cleared Contracts	4,449,856		5,761,558
Stock options and futures [Member]
Clearing Operations [Line Items]
Market value of derivative contracts	178	[1],[2]
Total Number of Cleared Contracts	9,981,753		8,809,147
Index options and futures [Member]
Clearing Operations [Line Items]
Market value of derivative contracts	$222	[1],[2]
Total Number of Cleared Contracts	13,115,693		9,970,534
[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.
[4]	The total volume in cleared power related to commodity contracts was 363 Terawatt hours (TWh) for the three months ended March 31, 2015 and 429 TWh for the three months ended March 31, 2014.

Clearing_Operations_Schedule_o2

Clearing Operations (Schedule of Derivative Contracts Outstanding Additional Information) (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
	TW	TW
Clearing Operations [Abstract]
Total volume in cleared power, in Terawatt hours (TWh)	363	429

Commitments_Contingencies_and_1

Commitments, Contingencies and Guarantees (Details) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Line Items]
Financial guarantees obtained	$14	$14
Line of credit, outstanding amount		7
Margin deposits contributed to Cantor Fitzgerald	19
Legal Reserve [Member]
Commitments and Contingencies Disclosure [Line Items]
Legal And Other Expenses	31
eSpeed [Member]
Commitments and Contingencies Disclosure [Line Items]
Contingent future issuance of common stock, shares	992,247
Consolidated Amount of Revenue required to triger annual issuance of Nasdaq common stock	25
OCC [Member]
Commitments and Contingencies Disclosure [Line Items]
Payments to Acquire Equity Method Investments	30
Contribution In Equity Capital	150
Annual dividend From Shareholders percentage	50.00%
Clearinghouse Credit Facilities [Member]
Commitments and Contingencies Disclosure [Line Items]
Credit facilities, total	179	236
Line of credit facility, available liquidity	179	197
Credit facility, regulatory requirements amount		39
Line of credit, outstanding amount	0	7
Escrow Agreement [Member]
Commitments and Contingencies Disclosure [Line Items]
Contingency, accrual	9
Property Lease Guarantee [Member]
Commitments and Contingencies Disclosure [Line Items]
Other guarantees	$12	$13

Business_Segments_Narrative_De

Business Segments (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
	segment
Segment Reporting Information [Line Items]
Merger expenses		$28
Total restructuring charges	150	0
Amortization Of Intangible Assets	15	18
Number of Operating Segments	4
Legal Reserve [Member]
Segment Reporting Information [Line Items]
Special legal expenses	31
SE | Swedish Tax Agency [Member]
Segment Reporting Information [Line Items]
Tax expense (benefits) recorded	$12

Business_Segments_Schedule_of_

Business Segments (Schedule of Operating Segments) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Total revenues	$858	$898
Transaction-based expenses	-351	-369
Revenues less transaction rebates, brokerage, clearance and exchange fees	507	529
Operating income (loss)	27	184
Corporate Items and Eliminations [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	-208	-48
Market Services [Member]
Segment Reporting Information [Line Items]
Total revenues	539	577
Transaction-based expenses	-351	-369
Revenues less transaction rebates, brokerage, clearance and exchange fees	188	208
Operating income (loss)	101	105
Listing Services [Member]
Segment Reporting Information [Line Items]
Total revenues	64	58
Revenues less transaction rebates, brokerage, clearance and exchange fees	64	58
Operating income (loss)	28	22
Information Services [Member]
Segment Reporting Information [Line Items]
Total revenues	125	123
Revenues less transaction rebates, brokerage, clearance and exchange fees	125	123
Operating income (loss)	92	92
Technology Solutions [Member]
Segment Reporting Information [Line Items]
Total revenues	130	140
Revenues less transaction rebates, brokerage, clearance and exchange fees	130	140
Operating income (loss)	$14	$13

Subsequent_Event_Details

Subsequent Event (Details) (USD $)	3 Months Ended		1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Apr. 30, 2015
Subsequent Event [Line Items]
Common Stock Dividends Per Share Declared	$0.15	$0.28
Subsequent Event [Member]
Subsequent Event [Line Items]
Common Stock Dividends Per Share Declared			$0.25
Increase from prior quarter cash dividend, percentage			67.00%