Related Party Transactions - Cantor Rights to Purchase Cantor Units from BGC Holdings (Details) - Related Party - USD ($)	Jun. 30, 2023	Apr. 16, 2023	Oct. 25, 2022	May 17, 2022	Oct. 28, 2021	Mar. 31, 2021	Jun. 05, 2015
Related Party Transaction [Line Items]
Number of shares, right to exchange from Class A to Class B common stock (in shares)							34,600,000
BGC Holdings LPUs
Related Party Transaction [Line Items]
Number of founding partner interests as result of redemption (in shares)	5,425,209	533,757	275,833	427,494	460,929	1,149,684
Aggregate related party units (in shares)	324,223	85,775	77,507	52,681	1,179,942	1,618,376
Number of founding partner interests exchanged (in shares)	324,223	85,775	77,507	52,681	1,179,942	1,618,376
Aggregate related party units as result of redemption (in shares)	5,425,209	533,757	275,833	427,494	460,929	1,149,684
Aggregate consideration of related party units as result of redemption (in shares)	$ 9,715,772	$ 1,051,080	$ 397,196	$ 841,010	$ 715,605	$ 2,104,433
Aggregate consideration of Cantor Units	$ 598,712	$ 173,154	$ 142,613	$ 105,867	$ 2,033,838	$ 3,040,411
Maximum
Related Party Transaction [Line Items]
Number of shares, right to exchange from Class A to Class B common stock (in shares)							34,600,000