Segment and Geographic Information - Schedule of Product Information Regarding Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Total revenues	$ 2,262,818	$ 2,025,401	$ 1,795,302
Fees from related parties	20,728	15,968	14,734
Data, network and post-trade	126,963	111,470	96,389
Interest and dividend income	56,223	45,422	21,007
Other revenues	20,658	19,917	16,371
Compensation and employee benefits	1,123,747	992,603	853,165
Equity-based compensation and allocations of net income to limited partnership units and FPUs	369,143	355,378	251,071
Total compensation and employee benefits	1,492,890	1,347,981	1,104,236
Consolidated net income (loss)	123,228	38,775	58,867
Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	2,262,818	2,025,401	1,795,302
Fees from related parties	20,728	15,968	14,734
Data, network and post-trade	126,963	111,470	96,389
Interest and dividend income	56,223	45,422	21,007
Other revenues	20,658	19,917	16,371
Compensation and employee benefits	1,123,747	992,603	853,165
Equity-based compensation and allocations of net income to limited partnership units and FPUs	369,143	355,378	251,071
Total compensation and employee benefits	1,492,890	1,347,981	1,104,236
Other segment items	646,700	638,645	632,199
Consolidated net income (loss)	123,228	38,775	58,867
Interest income	49,500	40,200	15,500
Depreciation and intangible amortization	81,400	80,400	75,100
Total brokerage revenues | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	2,038,246	1,832,624	1,646,801
Rates | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	686,342	610,451	549,503
ECS | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	483,232	386,206	291,665
FX | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	355,833	314,706	299,721
Credit | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	287,812	284,744	271,419
Equities | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	225,027	236,517	234,493
Total other revenues | Reportable Segment
Segment Reporting Information [Line Items]
Total revenues	$ 224,572	$ 192,777	$ 148,501