Interest Income and Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Interest Income (Expense), Net [Abstract]
Loans held for investment, net	$ 1,253,008	$ 752,273	$ 378,086
Investment securities	467,199	247,755	129,858
Interest-bearing cash and federal funds sold	123,363	29,996	3,794
Margin balances	61,138	43,751	25,780
Financial instruments owned	16,726	20,545	15,041
Other	34,311	4,795	(4,159)
Total interest income	1,955,745	1,099,115	548,400
Bank deposits	724,857	146,636	4,510
Senior notes	50,025	44,424	47,500
Other	35,454	10,327	(6,012)
Total interest expense	$ 810,336	$ 201,387	$ 45,998