Fair Value Measurements - Unobservable Inputs Assumptions - Loans Held for Investment (Details) - Level 3 - Loans held for investment, at fair value	Mar. 31, 2025	Dec. 31, 2024
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Coupon, Base Rate	5.80%	6.20%
Coupon, Actual	5.90%	5.90%
FICO, Base Rate	640	640
FICO, Actual	668	665
Loan-to-value (LTV), Base Rate	86.00%	86.00%
Loan-to-value (LTV), Actual	78.00%	78.00%
Single family
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	77.00%	78.00%
Manufactured housing
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	3.00%	3.00%
Multi-family/mixed use/other
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	20.00%	19.00%
Owner Occupied
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	84.00%	86.00%
Investor
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	11.00%	9.00%
Secondary
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	5.00%	5.00%