Related Party Transactions - Service Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Total revenues	$ 2,941,460	$ 2,262,818	$ 2,025,401
Tower Bridge International Services LP | BGC Partners, Inc.
Related Party Transaction [Line Items]
Company ownership of Tower Bridge	52.00%
Tower Bridge International Services LP | Cantor
Related Party Transaction [Line Items]
Ownership percentage by noncontrolling owners	48.00%
Related Party
Related Party Transaction [Line Items]
Mark-up cost of services	7.50%
Share of net profit (loss) from noncontrolling interest	$ 2,800	2,200	2,800
Compensation to leased employees	103,600	75,100	64,700
Related Party | Service Agreement With Cantor
Related Party Transaction [Line Items]
Total revenues	18,700	20,700	16,000
Service charges	$ 141,900	$ 107,600	$ 97,400