Fair Value Measurements - Unobservable Inputs Assumptions - Loans Held for Investment (Details) - Loans Held for Investment at Fair Value - Level 3	Jun. 30, 2023	Dec. 31, 2022
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Coupon	5.90%	5.80%
FICO	664	656
Loan-to-value (LTV)	79.00%	82.00%
Single family
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	79.00%	80.00%
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	18.00%	17.00%
Owner Occupied
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	87.00%	89.00%
Investor
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	9.00%	5.00%
Secondary
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Weighted average percent	5.00%	6.00%
Base Rate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Coupon	6.30%	6.30%
FICO	640	640
Loan-to-value (LTV)	86.00%	87.00%