Related Party Transactions - Service Agreements and Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Related Party Transaction
Fees to related parties	$ 6,748	$ 5,782	$ 13,577	$ 12,032
Loans, forgivable loans and other receivables from employees and partners, net	478,365		478,365		$ 453,345
Labor and related expense	468,605	808,929	868,087	1,112,251
Employee Loans
Related Party Transaction
Loans, forgivable loans and other receivables from employees and partners, net	478,400		478,400		$ 453,300
Labor and related expense	20,700	19,500	39,600	36,800
Cantor Fitzgerald Limited Partnership And B G C Partners Incorporation
Related Party Transaction
Fees to related parties	$ 6,700	$ 5,800	$ 13,600	$ 12,000

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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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