Commitments and Contingencies Disclosure [Line Items]

No definition available.

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- Definition

Minimum amount of revenue required to trigger annual issuance of stock

+ References

No definition available.

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- Definition

Credit Facility Available Liquidity

+ References

No definition available.

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- Definition

Financial guarantees obtained to provide further liquidity and default protection related to clearing businesses

+ References

No definition available.

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- Definition

Number Of National Exchanges Named As Defendants

+ References

No definition available.

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- Definition

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

+ References

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Period Type:	instant

- Definition

Amount of loss contingency liability.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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- Definition

Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

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- Definition

Number of shares of stock issued during the period pursuant to acquisitions.

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Commitments, Contingencies and Guarantees (Details)		3 Months Ended
Commitments, Contingencies and Guarantees (Details)	Sep. 02, 2014 exchange	Mar. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($)	Oct. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Line Items]
Financial guarantees obtained		$ 10,000,000	$ 11,000,000
National exchanges named as defendants (in exchanges) \| exchange	7
Estimate of possible loss of revenue				$ 1,000,000
eSpeed
Commitments and Contingencies Disclosure [Line Items]
Contingent future issuance of common stock (in shares) \| shares		992,247
Revenue required to trigger annual issuance of Nasdaq common stock		$ 25,000,000
Escrow Agreement
Commitments and Contingencies Disclosure [Line Items]
Contingency, accrual		5,000,000
ICBC
Commitments and Contingencies Disclosure [Line Items]
Margin deposits contributed to brokers		15,000,000
Clearinghouse Credit Facilities
Commitments and Contingencies Disclosure [Line Items]
Credit facility, available liquidity		193,000,000	203,000,000
Commercial Paper and Letter Of Credit \| Clearinghouse Credit Facilities
Commitments and Contingencies Disclosure [Line Items]
Utilized amount		$ 0	$ 15,000,000