Interest Income and Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Interest Income (Expense), Net [Abstract]
Loans held for investment, net	$ 320,715	$ 208,365	$ 928,801	$ 480,053
Investment securities	120,670	71,420	345,201	151,728
Interest-bearing cash and federal funds sold	35,560	7,745	83,280	11,721
Margin balances	15,651	12,510	45,874	28,154
Other	12,602	4,155	36,376	10,728
Total interest income	505,198	304,195	1,439,532	682,384
Bank deposits	198,197	43,371	506,847	47,899
Senior notes	12,507	11,220	37,519	33,919
Other	9,832	5,165	22,258	4,729
Total interest expense	$ 220,536	$ 59,756	$ 566,624	$ 86,547