v3.26.3
Mortgage Loans - Subsequent Defaults of Single-Family Restructured Loans Involving Borrowers Experiencing Financial Difficulty (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Single family        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default $ 2,398 $ 2,067 $ 5,814 $ 4,705
Single family | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 1,190 1,164 2,893 2,798
Single family | payment delay and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 985 834 2,477 1,811
Single family | payment delay, interest rate reduction, and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 223 69 444 96
20- and 30-year or more, amortizing fixed-rate        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 2,360 2,029 5,725 4,607
20- and 30-year or more, amortizing fixed-rate | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 1,154 1,128 2,810 2,703
20- and 30-year or more, amortizing fixed-rate | payment delay and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 983 832 2,471 1,808
20- and 30-year or more, amortizing fixed-rate | payment delay, interest rate reduction, and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 223 69 444 96
15-year or less, amortizing fixed-rate        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 26 29 64 75
15-year or less, amortizing fixed-rate | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 26 29 63 75
15-year or less, amortizing fixed-rate | payment delay and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 0 0 1 0
15-year or less, amortizing fixed-rate | payment delay, interest rate reduction, and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 0 0 0 0
Adjustable-rate and other        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 12 9 25 23
Adjustable-rate and other | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 10 7 20 20
Adjustable-rate and other | payment delay and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 2 2 5 3
Adjustable-rate and other | payment delay, interest rate reduction, and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default $ 0 $ 0 $ 0 $ 0