MPF Loans Held in Portfolio (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
MPF Loans held in portfolio, net	$ 13,905	$ 13,320
MPF Loans held in portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	13,736	13,161
Net premiums, credit enhancement, and/or deferred loan fees	189	186
Fair value hedging and delivery commitment basis adjustments	(16)	(22)
MPF Loans held in portfolio, before allowance for credit losses	13,909	13,325
Allowance for credit losses on MPF Loans	(4)	(5)
MPF Loans held in portfolio, net	13,905	13,320
MPF Loans held in portfolio \| Medium term (15 years or less)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	1,355	1,395
MPF Loans held in portfolio \| Long term (greater than 15 years)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	12,381	11,766
MPF Loans held in portfolio \| Conventional mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	12,787	12,319
MPF Loans held in portfolio \| Government Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid principal balance	$ 949	$ 842

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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