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Contribution to the financial markets.

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Nasdaq Clearing members cash contributions for regulatory capital requirements associated with default fund contributions and margin deposits.

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Highly Rated Government Debt Securities

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Junior capital, cash deposits and pledged assets.

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Liability Due To Market Default

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Number of member sponsored default funds

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Reverse Purchase Agreements, Maturity Date Range

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Senior capital, cash deposits and pledged assets.

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Temporary Capital

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Temporary Capital, Holding Time Period

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Total number of derivative contracts cleared

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Amount of investment in marketable security, classified as current.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period of time between issuance and maturity of customer deposits, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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Clearing Operations (Narrative) (Details) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
Clearing Operations (Narrative) (Details) $ in Millions	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) fund contract	Sep. 30, 2017 USD ($) contract	Dec. 31, 2017 USD ($)
Clearing Operations [Line Items]
Number of member sponsored default funds \| fund				4
Loss due to commodities market default	$ 133
Loss due to commodities market default allocated to junior capital	8
Temporary capital	22	$ 22		$ 22
Liability due to market default	56	56		56
Collateral due to market default	56	56		56
Default funds and margin deposits	4,219	4,219		4,219		$ 3,988
Default fund contributions	515	515		515
Committed capital	202	202		202		$ 235
Liability Waterfall
Clearing Operations [Line Items]
Loss due to commodities market default allocated to junior capital	8	8	$ 0	8	$ 0
Junior capital, cash deposits and pledged assets	31	31		31
Senior capital, cash deposits and pledged assets	22	22		22
Committed capital	67	67		67
Utilize as capital resources
Clearing Operations [Line Items]
Default fund contributions	463	463		463
Utilize as member posted surplus balance
Clearing Operations [Line Items]
Default fund contributions	52	52		52
Nasdaq Clearing
Clearing Operations [Line Items]
Temporary capital	22	22		$ 22
Temporary capital, holding time period				90 days
Default fund cash contributions invested in highly rated government debt securities				$ 1,187
Maturity period of time deposits				90 days
Committed capital	128	128		$ 128
Power of assessment of the clearing member's contribution to the financial markets and commodities markets default funds				100.00%
Contract value of resale and repurchase agreements	4,100	4,100	$ 5,000	$ 4,100	$ 5,000
Total number of derivative contracts cleared \| contract				6,835,634	5,891,900
Nasdaq Clearing \| Reverse Repurchase Agreements
Clearing Operations [Line Items]
Default funds and margin deposits	$ 430	$ 430		$ 430
Minimum
Clearing Operations [Line Items]
Reverse purchase agreements, maturity range				1 day
Maximum
Clearing Operations [Line Items]
Reverse purchase agreements, maturity range				19 days