XML 84 R71.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Stock Transactions and Unit Redemptions - Summary of Changes in Carrying Amount of Redeemable Partnership Interest (Detail) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Stock Transactions Parenthetical Disclosures [Abstract] |  |
Balance at beginning of period | $ 46,415 | $ 52,577
Consolidated net income allocated to FPUs | 1,009 | 1,054
Earnings distributions |  | (1,434)
FPUs exchanged |  | (303)
FPUs redeemed | (21) | (59)
Other | 102 | (2)
Balance at end of period | $ 47,505 | $ 51,833

X
- Definition Exchange Of Founding Working Partner Interests + References No definition available. + Details
Name: | bgcp_ExchangeOfFoundingWorkingPartnerInterests
Namespace Prefix: | bgcp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Redemption of founding working partner interests. + References No definition available. + Details
Name: | bgcp_RedemptionOfFoundingWorkingPartnerInterests
Namespace Prefix: | bgcp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The impact on temporary equity associated with the distribution of earnings. + References No definition available. + Details
Name: | bgcp_TemporaryEquityEarningsDistributions
Namespace Prefix: | bgcp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_StockTransactionsParentheticalDisclosuresAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.27(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The portion of net income or loss attributable to temporary equity interest. + References No definition available. + Details
Name: | us-gaap_TemporaryEquityNetIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of increase (decrease) in temporary equity from changes classified as other. + References No definition available. + Details
Name: | us-gaap_TemporaryEquityOtherChanges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration