Mortgage-Backed Securities - Loan Products Type and Characteristics (Details) - Non-Agency RMBS	Mar. 31, 2024	Dec. 31, 2023
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	12.50%	12.20%
Bankruptcy
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	1.30%	1.30%
Foreclosure
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	3.00%	3.00%
REO
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	0.60%	0.50%
30 Days Delinquent
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	3.70%	3.40%
60 Days Delinquent
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	1.50%	1.40%
90+ Days Delinquent
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
% of Unpaid Principal Balance	2.40%	2.60%