Debt Instrument, Remaining Authorized Purchase Amount

No definition available.

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

- Definition

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

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+ Details

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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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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Expense related to distribution, servicing and underwriting fees.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This represents the company's cost incurred during an accounting period for managing the money in a fund, which will be billed back to the client and is a component of noninterest expenses.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

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- Definition

Number of new stock issued during the period.

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Related Party Transactions - CEO Program and Other Transactions with CF&Co (Details) - USD ($) shares in Millions						3 Months Ended		6 Months Ended
	Jun. 10, 2024	May 25, 2023	Jul. 10, 2020	Sep. 27, 2019	Jul. 24, 2018	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 11, 2020
Related Party Transaction [Line Items]
Debt instrument, remaining authorized purchase amount						$ 50,000,000.0		$ 50,000,000.0
Maximum
Related Party Transaction [Line Items]
Purchased senior notes										$ 50,000,000
5.375% Senior Notes due 2023
Related Party Transaction [Line Items]
Principal amount of debt component					$ 450,000,000.0
Stated interest rate					5.375%
3.750% Senior Notes due 10/1/2024
Related Party Transaction [Line Items]
Principal amount of debt component				$ 300,000,000.0
Stated interest rate				3.75%
BGC Partners $4.375% Senior Notes due December 15, 2025
Related Party Transaction [Line Items]
Principal amount of debt component			$ 300,000,000.0
Stated interest rate			4.375%
BGC Group $8.000% Senior Notes due May 25, 2028
Related Party Transaction [Line Items]
Principal amount of debt component		$ 350,000,000
Stated interest rate		8.00%				8.00%		8.00%
BGC Group 6.600% Senior Notes due June 10, 2029
Related Party Transaction [Line Items]
Principal amount of debt component	$ 500,000,000
Stated interest rate	6.60%
Underwriting fees paid	$ 400,000
Related Party
Related Party Transaction [Line Items]
Related party expenses						$ 0	$ 0	$ 0	$ 0
Issuance of common stock (in shares)						0.0	0.0	0.0	0.0
Related Party \| 5.375% Senior Notes due 2023
Related Party Transaction [Line Items]
Advisory fees					$ 200,000
Related Party \| 5.375% Senior Notes due 2023 \| Underwriting fees
Related Party Transaction [Line Items]
Related party expenses					$ 300,000
Related Party \| 3.750% Senior Notes due 10/1/2024 \| Underwriting fees
Related Party Transaction [Line Items]
Related party expenses				$ 200,000
Related Party \| BGC Partners $4.375% Senior Notes due December 15, 2025
Related Party Transaction [Line Items]
Purchased senior notes						$ 14,500,000		$ 14,500,000
Related Party \| BGC Partners $4.375% Senior Notes due December 15, 2025 \| Underwriting fees
Related Party Transaction [Line Items]
Related party expenses			$ 200,000
Related Party \| BGC Group $8.000% Senior Notes due May 25, 2028 \| Underwriting fees
Related Party Transaction [Line Items]
Related party expenses		$ 200,000