Stock or Units Repurchase Program, Authorized Amount

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Period Type:

- Details

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Namespace Prefix:
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Subsequent Events (Detail) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended		6 Months Ended
	Aug. 03, 2021	Jul. 30, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Subsequent Event [Line Items]
Dividends declared per share of common stock (in dollars per share)			$ 0.01	$ 0.01	$ 0.02	$ 0.15
Subsequent Event
Subsequent Event [Line Items]
Stock or units repurchase program, authorized amount	$ 400.0
Subsequent Event \| Cantor Futures Exchange Business
Subsequent Event [Line Items]
Payments to acquire businesses		$ 4.9
Class A Common Stock \| Subsequent Event
Subsequent Event [Line Items]
Dividends declared per share of common stock (in dollars per share)	$ 0.01
Class B Common Stock \| Subsequent Event
Subsequent Event [Line Items]
Dividends declared per share of common stock (in dollars per share)	$ 0.01