Fixed assets pledged for secured loan value.

No definition available.

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Namespace Prefix:	bgcp_
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Balance Type:	debit
Period Type:	instant

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

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Schedule I - Parent Company Only - Commitments, Contingencies and Guarantees - Additional Information (Detail) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Apr. 19, 2019	Apr. 08, 2019	May 31, 2017	Jul. 10, 2015	Mar. 13, 2015
3.70% loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount							$ 28,200,000
Stated interest rate							3.70%
Outstanding balance of the secured loan arrangements	$ 0	$ 0
3.44% loan
Loss Contingencies [Line Items]
Outstanding balance of the secured loan arrangements	0	4,000,000
3.44% loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount					$ 29,900,000
Stated interest rate					3.44%
Outstanding balance of the secured loan arrangements	0	4,000,000
Book value of the fixed assets pledged		800,000
3.77% loan
Loss Contingencies [Line Items]
Outstanding balance of the secured loan arrangements	5,900,000	9,600,000
3.77% loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount				$ 15,000,000
Stated interest rate				3.77%
Outstanding balance of the secured loan arrangements	5,900,000	9,600,000
Book value of the fixed assets pledged	100,000	1,200,000
3.89% Loan
Loss Contingencies [Line Items]
Outstanding balance of the secured loan arrangements	3,800,000	6,300,000
3.89% Loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount			$ 10,000,000
Stated interest rate			3.89%
Outstanding balance of the secured loan arrangements	3,800,000	6,300,000
Book value of the fixed assets pledged	1,000,000	2,700,000
Parent Company \| 3.70% loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount							$ 28,200,000
Stated interest rate							3.70%
Outstanding balance of the secured loan arrangements	0	0
Parent Company \| 8.375% Senior Notes \| Guarantee Obligations
Loss Contingencies [Line Items]
Stated interest rate						8.375%
Principal amount of notes						$ 240,000,000
Parent Company \| 3.44% loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount					$ 29,900,000
Stated interest rate					3.44%
Book value of the fixed assets pledged		800,000
Parent Company \| 3.77% loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount				$ 15,000,000
Stated interest rate				3.77%
Book value of the fixed assets pledged	100,000	1,200,000
Parent Company \| 3.89% Loan \| Secured Debt
Loss Contingencies [Line Items]
Debt instrument gross amount			$ 10,000,000
Stated interest rate			3.89%
Book value of the fixed assets pledged	$ 1,000,000	$ 2,700,000