Advances (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Federal Home Loan Bank, Advances [Line Items]
Advances	$ 110,230	$ 99,951
Advances, Par Value	$ 110,178	$ 100,730
Concentration Risk, Market Risk	The Bank’s advances are primarily concentrated in commercial banks and insurance companies.	The Bank’s advances are primarily concentrated in commercial banks and insurance companies.
Conventional Mortgage Loans [Member]
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Past Due	$ 14,185	$ 11,531
Conventional Mortgage Loans [Member] \| Financial Asset, Past Due
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Past Due	146	108
Athene Annuity and Life Company
Federal Home Loan Bank, Advances [Line Items]
Advances	$ 23,271
Advance Percent	21.00%
Athene Annuity and Life Company \| Conventional Mortgage Loans [Member]
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Past Due	$ 0
Wells FargoBank N.A.
Federal Home Loan Bank, Advances [Line Items]
Advances	$ 16,000	15,571
Advance Percent	15.00%
Wells FargoBank N.A. \| Conventional Mortgage Loans [Member]
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Past Due	$ 5
Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Past Due	0	0
Financing Receivable, Non-Accrual	0	0
Financing Receivable, Modified, Accumulated	0	0
Financing Receivable, Allowance for Credit Losses	$ 0	$ 0
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Accrued interest receivable	Accrued interest receivable
Financing Receivable, Accrued Interest, after Allowance for Credit Loss	$ 192	$ 180
Minimum [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, Advances, Maturity Period, Variable Rate	1 month
Maximum [Member]
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, Advances, Maturity Period, Fixed Rate	30 years
Federal Home Loan Bank, Advances, Maturity Period, Variable Rate	10 years
Federal Home Loan Bank, Advances, Callable Option [Member]
Federal Home Loan Bank, Advances [Line Items]
Advances, Par Value	$ 10,600	$ 10,400

Concentration of advances by percent.

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Description of risks that arise due to the volume of transactions the entity executes within a particular (nongeographic) market. The description may address the risks inherent in the market, and, at a minimum, informs financial statement users of the general nature of the risk.

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Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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Maturity period on fixed rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Par amount of advances made and reported by Federal Home Loan Bank (FHLBank).

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Amount, after allowance for credit loss, of accrued interest on financing receivable.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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