Loans Held for Investment and Loans Held for Investment at Fair Value - Summary of Loans Held for Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts Notes And Loans Receivable [Line Items]
Allowance for loan losses	$ (4,769)	$ (4,893)	$ (4,262)
Net Loans Held For Investment
Accounts Notes And Loans Receivable [Line Items]
Unpaid principal balance	2,804,541	3,243,854
Deferred loan origination costs	28,351	33,429
Total loans held for investment and loans held for investment at fair value, gross	2,832,892	3,277,283
Allowance for loan losses	(4,769)	(4,893)
Total loans held for investment, net	2,828,123	3,272,390
Loans At Fair Value Held For Investment
Accounts Notes And Loans Receivable [Line Items]
Unpaid principal balance	1,251,395	268,632
Valuation adjustments on FVO loans	54,677	7,463
Total loans held for investment and loans held for investment at fair value, gross	1,306,072	276,095
Total loans held for investment, net	1,306,072	276,095
Total Loans Held For Investment
Accounts Notes And Loans Receivable [Line Items]
Unpaid principal balance	4,055,936	3,512,486
Valuation adjustments on FVO loans	54,677	7,463
Deferred loan origination costs	28,351	33,429
Total loans held for investment and loans held for investment at fair value, gross	4,138,964	3,553,378
Allowance for loan losses	(4,769)	(4,893)
Total loans held for investment, net	$ 4,134,195	$ 3,548,485