Advances (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Federal Home Loan Bank, Advances [Line Items]
Advances	$ 127,032	$ 110,230
Federal Home Loan Bank, Advances, Par Value	$ 127,223	110,178
Concentration Risk, Market Risk	The Bank’s advances are primarily concentrated in commercial banks and insurance companies.
Athene Annuity and Life Company
Federal Home Loan Bank, Advances [Line Items]
Advances	$ 28,221	23,271
Financing Receivable, Allowance for Credit Loss, Noncurrent		0
Advance Percent	22.00%
Wells Fargo Bank N.A.
Federal Home Loan Bank, Advances [Line Items]
Advances	$ 30,000	16,000
Advance Percent	24.00%
Federal Home Loan Bank Advances [Member]
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Accrued Interest, after Allowance for Credit Loss	$ 207	192
Financing Receivable, Nonaccrual	0	0
Financing Receivable, Troubled Debt Restructuring	0	0
Financing Receivable, Allowance for Credit Loss	$ 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, Allowance for Credit Loss, Noncurrent	$ 0	$ 0

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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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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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, 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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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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