Loans Held for Investment and Loans Held for Investment at Fair Value - Summary of UPB and Amortized Cost Basis of Loans in COVID-19 Forbearance Program (Details) - COVID 19 Forbearance Program - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Accounts Notes And Loans Receivable [Line Items]
UPB Beginning balance	$ 195,114	$ 201,005	$ 292,429
UPB Foreclosures		(99)	(3,593)
UPB Repayments	(13,175)	(18,967)	(87,831)
UPB Ending balance	181,939	181,939	201,005
UPB Performing/Accruing, Amount	138,419	138,419	161,455
UPB Nonperforming/Nonaccrual, Amount	$ 43,520	$ 43,520	$ 39,550
UPB Performing/Accruing, Percentage	76.10%	76.10%	80.30%
UPB Nonperforming/Nonaccrual, Percentage	23.90%	23.90%	19.70%
Amortized Cost Beginning balance	$ 197,350	$ 203,346	$ 295,990
Amortized Cost Foreclosures		(99)	(3,620)
Amortized Cost Repayments	(13,343)	(19,240)	(89,024)
Amortized Cost Ending balance	184,007	184,007	203,346
Amortized Cost Performing/Accruing, Amount	139,941	139,941	163,346
Amortized Cost Nonperforming/Nonaccrual, Amount	$ 44,066	$ 44,066	$ 40,000
Amortized Cost Performing/Accruing, Percentage	76.10%	76.10%	80.30%
Amortized Cost Nonperforming/Nonaccrual, Percentage	23.90%	23.90%	19.70%