Mortgage Loans - Amortized Cost Basis of Held-for-Investment Loans on Nonaccrual (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Income Recognized	$ 362	$ 323
Financing Receivable, Excluding Accrued Interest, Nonaccrual	17,669	16,033	$ 13,522
Single Family
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Income Recognized	357	320
Financing Receivable, Excluding Accrued Interest, Nonaccrual	17,442	15,908	13,458
20- and 30-year or more, amortizing fixed-rate
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Income Recognized	345	307
Financing Receivable, Excluding Accrued Interest, Nonaccrual	16,739	15,157	12,682
15-year or less, amortizing fixed-rate
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Income Recognized	7	8
Financing Receivable, Excluding Accrued Interest, Nonaccrual	482	511	519
Adjustable-rate and other
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Income Recognized	5	5
Financing Receivable, Excluding Accrued Interest, Nonaccrual	221	240	257
Multifamily
Financing Receivable, Allowance for Credit Loss [Line Items]
Interest Income Recognized	5	3
Financing Receivable, Excluding Accrued Interest, Nonaccrual	$ 227	$ 125	$ 64