Goodwill acquired during period net of measurement period adjustments.

No definition available.

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Namespace Prefix:	bgcp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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-Section 30
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-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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)
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+ Details

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Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=bgcp_FuturesExchangeGroupMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions (Detail) - USD ($) $ in Millions		12 Months Ended
Acquisitions (Detail) - USD ($) $ in Millions	Jul. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Total consideration transferred		$ 4.9	$ 9.6
Goodwill acquired during period net of assets acquired			$ 2.8
Futures Exchange Group
Business Acquisition [Line Items]
Payments to acquire businesses	$ 4.9