Related Party Transactions - Service Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Total revenues	$ 2,262,818	$ 2,025,401	$ 1,795,302
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	$ 2,200	2,800	700
Total revenues	20,700	16,000	14,700
Service charges	107,600	97,400	84,900
Compensation to leased employees	$ 75,100	$ 64,700	$ 59,200

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