Loans Held for Investment - Percentage of Securitized Loans Held For Investment Carried at Fair Value by Year Originated (Details) - Seasoned Subprime Residential Mortgage Loans - Loans held for investment, at fair value	Mar. 31, 2025	Dec. 31, 2024
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	100.00%	100.00%
2002 and prior
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	4.90%	5.00%
2003
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	4.40%	4.40%
2004
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	8.30%	8.20%
2005
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	14.30%	14.10%
2006
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	18.20%	18.00%
2007
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	20.10%	20.90%
2008
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	6.00%	6.80%
2009
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	1.40%	1.70%
2010 and later
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Percentage of underlying mortgages, year originated	22.40%	20.90%