XML 123 R101.htm IDEA: XBRL DOCUMENT
v3.20.1

Compensation - Compensation Expense Related to Restricted Stock Unit Held by BGC Employees (Detail) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Compensation Related Costs [Abstract] |  |
RSU amortization | $ 1,582 | $ 1,014

X
- Definition Share based compensation arrangement by share based payment award restricted stock units amortization. + References No definition available. + Details
Name: | bgcp_ShareBasedCompensationArrangementByShareBasedPaymentAwardRestrictedStockUnitsAmortization
Namespace Prefix: | bgcp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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