Activities with Other FHLBanks (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Other Transactions [Line Items]
Payments for FHLBank Advance, Investing Activities	$ 695,392	$ 405,970	$ 580,732
Loans to Other Federal Home Loan Banks	0	0	0	$ 0
Payments for Federal Home Loan Bank Loans	1,670	205	5,160
Proceeds from Federal Home Loan Bank Loans	(1,670)	(205)	(5,160)
Loans from Other Federal Home Loan Banks	0	0	0	0
Proceeds from FHLBank Borrowings, Financing Activities	2,700	2,500	2,265
Payments of FHLBank Borrowings, Financing Activities	(2,700)	(2,500)	(2,265)
Interest-bearing deposits (Note 4)	3,726	4,096
Federal Home Loan Bank of Boston [Member]
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	0	0	0
Payments for Federal Home Loan Bank Loans	300	200
Proceeds from Federal Home Loan Bank Loans	(300)	(200)
Loans from Other Federal Home Loan Banks		0	0	0
Proceeds from FHLBank Borrowings, Financing Activities		2,000	450
Payments of FHLBank Borrowings, Financing Activities		(2,000)	(450)
Federal Home Loan Bank of Chicago [Member]
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	0	0	0	0
Payments for Federal Home Loan Bank Loans	10	5	2,005
Proceeds from Federal Home Loan Bank Loans	(10)	(5)	(2,005)
Loans from Other Federal Home Loan Banks	0	0
Proceeds from FHLBank Borrowings, Financing Activities	300
Payments of FHLBank Borrowings, Financing Activities	(300)
Loan Portfolio Expense	10	8	6
Interest-bearing deposits (Note 4)	6	1
Federal Home Loan Bank of San Francisco
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	0	0	0	0
Payments for Federal Home Loan Bank Loans	850		2,655
Proceeds from Federal Home Loan Bank Loans	(850)		(2,655)
Loans from Other Federal Home Loan Banks	0	0	0	0
Proceeds from FHLBank Borrowings, Financing Activities	500		500
Payments of FHLBank Borrowings, Financing Activities	(500)		(500)
Federal Home Loan Bank of Cincinnati
Schedule of Other Transactions [Line Items]
Loans from Other Federal Home Loan Banks	0	0	0	0
Proceeds from FHLBank Borrowings, Financing Activities	550	500	750
Payments of FHLBank Borrowings, Financing Activities	(550)	(500)	(750)
Federal Home Loan Bank of Topeka [Member]
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	0	0
Payments for Federal Home Loan Bank Loans	10
Proceeds from Federal Home Loan Bank Loans	(10)
Loans from Other Federal Home Loan Banks	0	0	0	0
Proceeds from FHLBank Borrowings, Financing Activities	450		565
Payments of FHLBank Borrowings, Financing Activities	(450)		(565)
Federal Home Loan Bank of New York
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks			0	$ 0
Payments for Federal Home Loan Bank Loans			500
Proceeds from Federal Home Loan Bank Loans			$ (500)
Loans from Other Federal Home Loan Banks	0	0
Proceeds from FHLBank Borrowings, Financing Activities	700
Payments of FHLBank Borrowings, Financing Activities	(700)
Federal Home Loan Bank of Indianapolis
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	0	0
Payments for Federal Home Loan Bank Loans	500
Proceeds from Federal Home Loan Bank Loans	(500)
Federal Home Loan Bank of Atlanta
Schedule of Other Transactions [Line Items]
Loans from Other Federal Home Loan Banks	0	$ 0
Proceeds from FHLBank Borrowings, Financing Activities	200
Payments of FHLBank Borrowings, Financing Activities	$ (200)

Amounts for the payment of Federal Home Loan Bank loans.

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Proceeds from Federal Home Loan Bank Loans

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Schedule of Other Transactions [Line Items]

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The loan servicing fees paid to third parties that relate to loan expenses for a portfolio containing the entire group of loans owned by the company.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
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Amount of Federal Home Loan Bank (FHLBank) loans from another FHLBank.

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Amount of Federal Home Loan Bank (FHLBank) loans to another FHLBank.

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Amount of cash outflow for disbursement to borrower related to advance, made by Federal Home Loan Bank (FHLBank), classified as investing activity.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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Amount of cash inflow from Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

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