Debt Instrument, Renewal Term

No definition available.

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

- Definition

Tendered amount on cash tender offer.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

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+ 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.

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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

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

+ References

+ Details

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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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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+ Details

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

- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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+ Details

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

- Definition

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

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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.

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- 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.

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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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Period Type:	duration

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- Details

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- Details

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Schedule I - Parent Company Only - Long Term Debt - Additional Information (Detail) - USD ($)						12 Months Ended
	Nov. 01, 2021	May 27, 2021	Jul. 10, 2020	Feb. 26, 2020	Sep. 27, 2019	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Aug. 11, 2020	Aug. 05, 2020	Nov. 28, 2018	Jul. 24, 2018	May 27, 2016
Debt Instrument [Line Items]
Total						$ 73,877,000
Debt, Long-term and Short-term, Combined Amount						1,051,134,000	$ 1,056,415,000
Interest expense						57,932,000	69,329,000	$ 76,607,000
Parent Company
Debt Instrument [Line Items]
Interest expense						53,652,000	60,772,000	65,762,000
5.125% Senior Notes due May 27, 2021
Debt Instrument [Line Items]
Total						$ 0
Stated interest rate						5.125%
5.125% Senior Notes due May 27, 2021 \| Parent Company
Debt Instrument [Line Items]
Total							5,800,000	16,300,000
Principal amount of notes													$ 300,000,000
Repayments of outstanding borrowings		$ 256,000,000
Stated interest rate						5.125%
5.375% Senior Notes due July 24, 2023
Debt Instrument [Line Items]
Stated interest rate						5.375%						5.375%
5.375% Senior Notes due July 24, 2023 \| Parent Company
Debt Instrument [Line Items]
Total						$ 25,500,000	25,500,000	25,500,000
Principal amount of notes												$ 450,000,000
Redemption price as percentage of principal amount						101.00%
Debt, Long-term and Short-term, Combined Amount						$ 449,200,000						444,200,000
Debt issuance costs												$ 5,800,000
Stated interest rate												5.375%
3.750% Senior Notes due October 1, 2024
Debt Instrument [Line Items]
Total						$ 12,100,000	12,100,000	12,100,000
Stated interest rate						3.75%
3.750% Senior Notes due October 1, 2024 \| Parent Company
Debt Instrument [Line Items]
Principal amount of notes					$ 300,000,000
Redemption price as percentage of principal amount					101.00%
Debt, Long-term and Short-term, Combined Amount					$ 296,100,000	$ 298,600,000
Debt issuance costs					$ 3,900,000
Stated interest rate					3.75%
4.375% Senior Notes due December 15, 2025
Debt Instrument [Line Items]
Principal amount of notes			$ 300,000,000
Redemption price as percentage of principal amount			101.00%
Debt, Long-term and Short-term, Combined Amount			$ 296,800,000			298,200,000
Debt issuance costs			$ 3,200,000
Interest expense						$ 13,800,000	13,800,000	6,500,000
Stated interest rate			4.375%			4.375%
Cash Tender Offer \| 5.125% Senior Notes due May 27, 2021 \| Parent Company
Debt Instrument [Line Items]
Principal amount of notes										$ 300,000,000
Tendered amount on cash tender offer									$ 44,000,000
Stated interest rate										5.125%
New Senior Revolving Credit Agreement \| Unsecured Credit Agreement November 28, 2018 \| Parent Company
Debt Instrument [Line Items]
Maximum revolving credit											$ 350,000,000
Debt instrument, renewal term				2 years
Repayment of outstanding borrowings	$ 300,000,000
Line of credit facility, outstanding amount						$ 0	$ 0
Average interest rate						0.00%	2.09%
Total						$ 2,300,000	$ 3,600,000	$ 5,300,000