REGULATORY CAPITAL (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($) Test
Cboe Trading
Regulatory Requirement
Capital	$ 20.7
Minimum Requirement	0.7
BIDS Trading
Regulatory Requirement
Capital	12.2
Minimum Requirement	$ 0.9
Cboe Trading and BIDS Trading
Regulatory Requirement
Minimum net capital required to be maintained, option 1 - percentage of aggregate indebtedness items	6.67%
Minimum net capital required to be maintained, option 2 - amount	$ 0.1
Cboe Europe
Regulatory Requirement
Capital	65.0
Minimum Requirement	27.4
Cboe Chi-X Europe
Regulatory Requirement
Capital	0.4
Minimum Requirement	0.1
Capital resources requirement	0.1
Cboe Europe NL
Regulatory Requirement
Capital	8.6
Minimum Requirement	4.0
Cboe SEF
Regulatory Requirement
Annual operating expenses for swap execution facility capital adequacy tests	0.8
Three month operating expenses for swap execution facility capital adequacy tests	$ 0.2
Number of capital adequacy tests required to be met \| Test	2
CFE
Regulatory Requirement
Annual operating expenses for registered futures exchange capital adequacy tests	$ 49.8
Six month operating expenses for registered futures exchange capital adequacy tests	$ 24.9
Number of capital adequacy tests required to be met \| Test	2
EuroCCP
Regulatory Requirement
Capital	$ 53.2
Minimum Requirement	44.1
MATCHNow
Regulatory Requirement
Capital	3.6
Minimum Requirement	0.2
Chi-X Australia
Regulatory Requirement
Cash deposits	$ 4.4
Chi-X Japan
Regulatory Requirement
Minimum required regulatory capital ratio (as a percent)	120.00%
Regulatory capital ratio (as a percent)	262.00%

Capital Resources Requirement

No definition available.

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- Definition

Contract Markets, Annual Operating Expenses for Determination of Resource Adequacy

+ References

No definition available.

+ Details

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- Definition

Contract Markets, Six Month Operating Expenses for Determination of Resource Adequacy

+ References

No definition available.

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- Definition

Minimum amount of regulatory capital required by Japanese Financial Services Agency ("JFSA") and the Japan Securities Dealers Association ("JSDA").

+ References

No definition available.

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- Definition

Amount of minimum net capital required to be maintained.

+ References

No definition available.

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- Definition

Amount of minimum net capital required to be maintained based on percentage of aggregate indebtedness items.

+ References

No definition available.

+ Details

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- Definition

The number of capital adequacy tests required to be met.

+ References

No definition available.

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- Definition

Regulatory capital ratio.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Swap Execution Facility, Operating Expenses for Determination of Resource Adequacy

+ References

No definition available.

+ Details

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- Definition

Swap Execution Facility, Six Month Operating Expenses for Determination of Resource Adequacy

+ References

No definition available.

+ Details

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- Definition

Amount of total capital as defined by regulatory framework.

+ References

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- Definition

Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment in the future.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

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