CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Equity-based compensation (in shares)	15,838,276	14,758,605	3,284,120
Grant of exchangeability and redemption of limited partnership interests (in shares)		29,118,664	30,998,136
Repurchase of class A common stock (in shares)	36,200,000	24,220,000
Forfeitures of restricted Class A common stock (in shares)	300,000	1,400,000
Cantor purchase of Cantor units from BGC Holdings upon redemption of FPUs (in shares)		6,368,964	833,515
Dividends declared per share of common stock (in dollars per share)	$ 0.07	$ 0.04	$ 0.04
Dividends declared and paid per share of common stock (in dollars per share)	$ 0.07	$ 0.04	$ 0.04
Restricted stock awards (in shares)	0	38,610,233
Conversion of Class B common stock to Class A common stock (in shares)	1,061,665	405,801
Cancellation of BGC Partners, Inc. Treasury Stock due to Corporate Conversion (in shares)		156,386,616
Smith Mack
Issuance of Class A common stock and RSUs for acquisitions (in shares)		5,504,698
Partnership Units
Redemption of FPUs (in shares)		184,990	113,203
Class A Common Stock
Grant of exchangeability and redemption of limited partnership interests (in shares)	1,756,000	30,754,000
Issuance of common stock (in shares)	314,591	518,191	500,697
Repurchase of class A common stock (in shares)	31,573,031	23,250,551	27,086,884
Forfeitures of restricted Class A common stock (in shares)	1,439,575	1,428,363
Issuance of Class A common stock and RSUs for acquisitions (in shares)	1,062,000	4,566,000
Forfeiture of Class A common stock (in shares)			66,693
Cantor units converted into shares of BGC Group Class B common stock due to the Corporate Conversion (in shares)	1,800,000	20,500,000
Class A Common Stock | Smith Mack
Issuance of Class A common stock and RSUs for acquisitions (in shares)			1,205,767
Class B Common Stock
Issuance of common stock (in shares)	0	64,000,000
Cantor units converted into shares of BGC Group Class B common stock due to the Corporate Conversion (in shares)		63,974,374