Concentration of advances by percent

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- Definition

Amounts for the payment of Federal Home Loan Bank loans.

+ References

No definition available.

+ Details

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- Definition

Proceeds from Federal Home Loan Bank Loans

+ References

No definition available.

+ Details

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- Definition

Schedule of Other Transactions [Line Items]

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of cash inflow from Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

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- Definition

Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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Activities with Other FHLBanks (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	$ 0	$ 0	$ 0	$ 0
Proceeds from Federal Home Loan Bank Loans	(401)	(805)
Payments for Federal Home Loan Bank Advances	$ 401	805
Loans from Other Federal Home Loan Banks		0		0
Proceeds from FHLBank Borrowings, Financing Activities		1,500
Payments of FHLBank Borrowings, Financing Activities		(1,500)
Wells Fargo Bank N.A.
Schedule of Other Transactions [Line Items]
Advance Percent	24.00%
Federal Home Loan Bank of Chicago
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	$ 0		0
Proceeds from Federal Home Loan Bank Loans	(1)
Payments for Federal Home Loan Bank Advances	1
Loans from Other Federal Home Loan Banks		0		0
Proceeds from FHLBank Borrowings, Financing Activities		5
Payments of FHLBank Borrowings, Financing Activities		(5)
Federal Home Loan Bank of San Francisco
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks	0		$ 0
Proceeds from Federal Home Loan Bank Loans	(400)
Payments for Federal Home Loan Bank Advances	$ 400
Loans from Other Federal Home Loan Banks		0		0
Proceeds from FHLBank Borrowings, Financing Activities		500
Payments of FHLBank Borrowings, Financing Activities		(500)
Federal Home Loan Bank of Cincinnati
Schedule of Other Transactions [Line Items]
Loans from Other Federal Home Loan Banks		0		0
Proceeds from FHLBank Borrowings, Financing Activities		250
Payments of FHLBank Borrowings, Financing Activities		(250)
Federal Home Loan Bank of New York
Schedule of Other Transactions [Line Items]
Loans from Other Federal Home Loan Banks		0		0
Proceeds from FHLBank Borrowings, Financing Activities		500
Payments of FHLBank Borrowings, Financing Activities		(500)
Federal Home Loan Bank of Boston [Member]
Schedule of Other Transactions [Line Items]
Loans to Other Federal Home Loan Banks		0		0
Proceeds from Federal Home Loan Bank Loans		(300)
Payments for Federal Home Loan Bank Advances		300
Federal Home Loan Bank of Topeka [Member]
Schedule of Other Transactions [Line Items]
Loans from Other Federal Home Loan Banks		0		$ 0
Proceeds from FHLBank Borrowings, Financing Activities		250
Payments of FHLBank Borrowings, Financing Activities		$ (250)