Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenues:
Commissions	$ 395,081	$ 348,720	$ 810,253	$ 726,008
Principal transactions	98,439	94,883	211,288	209,812
Fees from related parties	4,643	4,062	9,064	8,019
Data, network and post-trade	30,812	27,000	61,715	54,122
Interest and dividend income	17,145	13,371	26,909	18,686
Other revenues	4,641	5,044	10,146	9,300
Total revenues	550,761	493,080	1,129,375	1,025,947
Expenses:
Compensation and employee benefits	271,990	243,387	562,832	510,601
Equity-based compensation and allocations of net income to limited partnership units and FPUs	66,207	126,644	162,288	208,017
Total compensation and employee benefits	338,197	370,031	725,120	718,618
Occupancy and equipment	40,959	40,488	81,765	81,653
Fees to related parties	8,009	7,991	15,224	16,431
Professional and consulting fees	12,805	14,819	27,064	30,520
Communications	30,172	27,813	60,180	55,752
Selling and promotion	17,714	15,320	34,485	29,936
Commissions and floor brokerage	17,414	16,161	34,806	31,426
Interest expense	21,551	19,914	41,687	35,656
Other expenses	13,334	13,221	27,892	25,729
Total expenses	500,155	525,758	1,048,223	1,025,721
Other income (losses), net:
Gains (losses) on equity method investments	2,744	2,412	4,534	4,474
Other income (loss)	1,814	(1,011)	40,576	(2,746)
Total other income (losses), net	4,558	1,401	45,110	1,728
Income (loss) from operations before income taxes	55,164	(31,277)	126,262	1,954
Provision (benefit) for income taxes	17,989	(9,067)	40,046	2,994
Consolidated net income (loss)	37,175	(22,210)	86,216	(1,040)
Less: Net income (loss) attributable to noncontrolling interest in subsidiaries	(653)	(2,506)	(822)	(314)
Net income (loss) available to common stockholders	37,828	(19,704)	87,038	(726)
Basic earnings (loss) per share
Net income (loss) attributable to common stockholders	$ 36,054	$ (19,704)	$ 82,502	$ (726)
Basic earnings (loss) per share (in dollars per share)	$ 0.08	$ (0.05)	$ 0.17	$ 0
Basic weighted-average shares of common stock outstanding (in shares)	475,272	391,745	472,895	383,528
Fully diluted earnings (loss) per share
Net income (loss) for fully diluted shares	$ 36,070	$ (19,704)	$ 82,553	$ (726)
Fully diluted earnings (loss) per share (in dollars per share)	$ 0.08	$ (0.05)	$ 0.17	$ 0
Fully diluted weighted-average shares of common stock outstanding (in shares)	480,861	391,745	479,417	383,528