Interest Income and Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Interest Income (Expense), Net [Abstract]
Loans held for investment, net	$ 150,351	$ 92,379	$ 271,688	$ 179,618
Investment securities	46,046	31,539	80,308	61,491
Margin balances	8,732	6,286	15,644	12,377
Financial instruments owned	4,057	2,543	9,477	5,438
Other	3,568	844	1,072	2,207
Total interest income	212,754	133,591	378,189	261,131
Senior notes	11,274	11,971	22,699	24,074
Bank deposits	3,599	1,214	4,528	2,497
Other	2,461	993	(436)	2,047
Total interest expense	$ 17,334	$ 14,178	$ 26,791	$ 28,618