Mortgage Loans - Loan Restructuring - Financial Impacts (Details) - Single-family	12 Months Ended
Dec. 31, 2025 USD ($) mo	Dec. 31, 2024 USD ($) mo	Dec. 31, 2023 USD ($) mo
20- and 30-year or more, amortizing fixed-rate
Loans in Mortgage Portfolio [Line Items]
Weighted-Average Interest Rate Reduction	0.57%	0.68%	1.06%
Weighted-Average Term Extension (in Months) \| mo	147	161	171
Average amount capitalized as a result of a payment delay \| $	$ 13,269	$ 13,000	$ 16,186
15-year or less, amortizing fixed-rate
Loans in Mortgage Portfolio [Line Items]
Weighted-Average Interest Rate Reduction	0.86%	1.77%	1.62%
Weighted-Average Term Extension (in Months) \| mo	51	80	72
Average amount capitalized as a result of a payment delay \| $	$ 9,762	$ 10,534	$ 14,236
Adjustable-rate
Loans in Mortgage Portfolio [Line Items]
Weighted-Average Interest Rate Reduction	0.87%	2.55%	1.62%
Weighted-Average Term Extension (in Months) \| mo	0	0	0
Average amount capitalized as a result of a payment delay \| $	$ 9,865	$ 10,710	$ 14,608
Other
Loans in Mortgage Portfolio [Line Items]
Weighted-Average Interest Rate Reduction	1.11%	0.82%	1.36%
Weighted-Average Term Extension (in Months) \| mo	148	168	189
Average amount capitalized as a result of a payment delay \| $	$ 13,787	$ 18,511	$ 20,910