Related Party Transactions - Service Agreements and Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Related Party Transaction
Fees to related parties	$ 7,301	$ 5,664	$ 20,878	$ 17,696
Loans, forgivable loans and other receivables from employees and partners, net	492,962		492,962		$ 453,345
Labor and related expense	432,991	478,371	1,301,078	1,590,622
Employee Loans
Related Party Transaction
Loans, forgivable loans and other receivables from employees and partners, net	493,000		493,000		$ 453,300
Labor and related expense	21,400	17,200	61,000	54,000
Cantor Fitzgerald Limited Partnership And B G C Partners Incorporation
Related Party Transaction
Fees to related parties	$ 7,300	$ 5,700	$ 20,900	$ 17,700

Amounts due from an Entity employee, not to include stockholders or officers, which are usually due after 1 year (or 1 business cycle).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=6457730&loc=d3e39599-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(4))
-URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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