Name:	bgcp_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityNetUnrealizedGainLossIncludedInNetIncomeLoss
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Fair value measurement with unobservable inputs reconciliation recurring basis liability net unrealized gain loss included in other comprehensive income (loss).

No definition available.

Name:	bgcp_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityNetUnrealizedGainLossIncludedInOtherComprehensiveIncomeLoss
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Fair value measurement with unobservable inputs reconciliation recurring basis liability purchases and issuances.

No definition available.

Name:	bgcp_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchasesAndIssuances
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Fair value measurement with unobservable inputs reconciliation recurring basis liability sales and settlements.

No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Amount of gain (loss) recognized in other comprehensive income (OCI) from liability measured at fair value on recurring basis using unobservable input (level 3).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482573/350-20-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 25
-Paragraph 16
-SubTopic 10
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479405/805-10-25-16