v3.26.1
Variable Interest Entities - Additional Information (Detail) - Credit Risk Transfer Agreements [Member]
3 Months Ended
Mar. 31, 2026
Minimum [Member]  
Mortgage Loans on Real Estate [Line Items]  
Initially established percentage of unpaid principal balance of loans sold under recourse obligation losses 3.50%
Increase to maximum percentage of outstanding unpaid principal balance 4.50%
Maximum [Member]  
Mortgage Loans on Real Estate [Line Items]  
Initially established percentage of unpaid principal balance of loans sold under recourse obligation losses 4.00%
Increase to maximum percentage of outstanding unpaid principal balance 5.00%