Debt Instrument, Extended Term

No definition available.

Name:	bgcp_DebtInstrumentExtendedTerm
Namespace Prefix:	bgcp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Non-extension Notice Term

+ References

No definition available.

+ Details

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Namespace Prefix:	bgcp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

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-Topic 835
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-Name Accounting Standards Codification
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-Topic 835
-SubTopic 30
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-Section 45
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

+ Details

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

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
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+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate amount of interest paid or due on all long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph a
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Number 229
-Section 1402
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-Subparagraph (1)
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-Topic 942
-SubTopic 220
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(8))
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-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

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

- Definition

Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1)(e))
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-Topic 946
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+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-SubTopic 210
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-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

+ Details

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Topic 946
-SubTopic 220
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-Section S99
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-Topic 946
-SubTopic 220
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-Topic 946
-SubTopic 220
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-Section S99
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-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (b)
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-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Period Type:

- Details

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Data Type:	na
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- Details

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- Details

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- Details

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Related Party Transactions - BGC Credit Agreement (Details) - USD ($)							3 Months Ended			6 Months Ended
	Jun. 10, 2024	Jun. 07, 2024	Apr. 01, 2024	Mar. 12, 2024	Mar. 08, 2024	Mar. 19, 2018	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Aug. 06, 2018
Related Party
Related Party Transaction [Line Items]
Interest income							$ 2,600,000		$ 2,100,000	$ 5,800,000	$ 3,900,000
Revolving credit facility \| BGC Credit Agreement \| Related Party
Related Party Transaction [Line Items]
Principal amount of debt component		$ 400,000,000			$ 400,000,000	$ 250,000,000.0							$ 400,000,000
Debt instrument, basis spread on variable rate					(0.25%)
Debt instrument, extended term					1 year
Debt instrument, non-extension notice term						6 months
Maturity term maximum		35 days
Repayment of outstanding borrowings			$ 275,000,000.0
Line of credit facility, outstanding amount			$ 275,000,000.0				0	$ 275,000,000.0		0		$ 0
Average interest rate					1.00%			6.92%
Interest expense recorded							0		0	1,100,000	0
Interest income							800,000		$ 0	800,000	$ 0
Proceeds from borrowings				$ 275,000,000
Revolving credit facility \| BGC Credit Agreement \| Related Party \| Cantor
Related Party Transaction [Line Items]
Line of credit facility, outstanding amount							$ 180,000,000			$ 180,000,000
Average interest rate										7.18%
Proceeds from borrowings	$ 180,000,000
Senior Revolving Credit Agreement \| Unsecured Credit Agreement
Related Party Transaction [Line Items]
Repayment of outstanding borrowings				$ 240,000,000
Average interest rate							7.17%		6.79%	7.18%	6.64%
Interest expense recorded							$ 4,200,000		$ 1,600,000	$ 7,900,000	$ 2,800,000