Revenue - Schedule of Collection Agency and Borrower Fees (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue from fees, net	$ 560,431	$ 907,272	$ 801,275
Net gain (loss) on servicing rights and fair value adjustments	(6,444)	22,891	11,030
Servicing fees
Disaggregation of Revenue [Line Items]
Revenue from fees, net	107,008	115,742	51,255
Borrower fees
Disaggregation of Revenue [Line Items]
Revenue from fees, net	29,139	25,208	7,289
Collection agency fees
Disaggregation of Revenue [Line Items]
Revenue from fees, net	15,865	10,519	4,473
Other fees
Disaggregation of Revenue [Line Items]
Revenue from fees, net	743	675	1,067
Servicing and other fees, net
Disaggregation of Revenue [Line Items]
Revenue from fees, net	$ 146,311	$ 175,035	$ 75,114