v3.26.1
Mortgage Loans - Subsequent Defaults of Single-Family Restructured Loans Involving Borrowers Experiencing Financial Difficulty (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Single family        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default $ 2,156 $ 1,691 $ 3,984 $ 3,074
Single family | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 1,058 1,031 1,980 1,892
Single family | payment delay and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 949 636 1,747 1,150
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 149 24 257 32
20- and 30-year or more, amortizing fixed-rate        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 2,119 1,652 3,919 2,996
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 1,025 993 1,919 1,816
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 945 635 1,743 1,148
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 149 24 257 32
15-year or less, amortizing fixed-rate        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 28 30 47 60
15-year or less, amortizing fixed-rate | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 27 30 46 60
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 1 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 9 9 18 18
Adjustable-rate and other | payment delay [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 6 8 15 16
Adjustable-rate and other | payment delay and term extension [Member]        
financing receivable, loan restructuring [Line Items]        
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default 3 1 3 2
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