v3.26.1
Mortgage Loans - Financial Effects of Single-Family Loan Restructurings Involving Borrowers Experiencing Financial Difficulty (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
20- and 30-year or more, amortizing fixed-rate        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Modified, Weighted-Average Interest Rate Decrease from Modification 0.80% 0.60% 0.80% 0.60%
Financing Receivable, Modified, Weighted-Average Term Increase from Modification 144 months 147 months 144 months 154 months
Weighted average payment deferral or principal forbearance $ 28 $ 26 $ 27 $ 21
15-year or less, amortizing fixed-rate        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Modified, Weighted-Average Interest Rate Decrease from Modification 0.00% 0.00% 0.00% 0.00%
Financing Receivable, Modified, Weighted-Average Term Increase from Modification 39 months 45 months 35 months 44 months
Weighted average payment deferral or principal forbearance $ 11 $ 11 $ 11 $ 10
Adjustable-rate and other        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Modified, Weighted-Average Interest Rate Decrease from Modification   1.00%   0.90%
Financing Receivable, Modified, Weighted-Average Term Increase from Modification 94 months 142 months 119 months 169 months
Weighted average payment deferral or principal forbearance $ 18 $ 16 $ 16 $ 13