Investments - Equity Method Investments and Investments Carried Under Measurement Alternative (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 41,221	$ 36,734
Investments carried under measurement alternative	7,155	1,031
Total equity method and investments carried under measurement alternative	$ 48,376	37,765
Advanced Markets Holdings
Schedule of Equity Method Investments [Line Items]
Percent ownership (as a percent)	25.00%
Equity method investments	$ 5,917	2,978
China Credit BGC Money Broking Company Limited
Schedule of Equity Method Investments [Line Items]
Percent ownership (as a percent)	33.00%
Equity method investments	$ 24,318	23,031
Freedom International Brokerage
Schedule of Equity Method Investments [Line Items]
Percent ownership (as a percent)	45.00%
Equity method investments	$ 9,858	9,683
Other
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 1,128	$ 1,042

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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