Advances (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, Advances, Par Value	$ 45,071,635	$ 41,875,692
Minimum [Member]
Federal Home Loan Bank, Advances [Line Items]
FHLB advances, outstanding interest rate	0.51%	0.44%
Maximum [Member]
Federal Home Loan Bank, Advances [Line Items]
FHLB advances, outstanding interest rate	7.20%	7.20%
Federal Home Loan Bank Advances Receivable [Member]
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Excluding Accrued Interest, Nonaccrual	$ 0	$ 0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Financing Receivable, Excluding Accrued Interest, Modified, Accumulated	0	0
FinancialAssetPastDue [Member] \| Federal Home Loan Bank Advances Receivable [Member]
Federal Home Loan Bank, Advances [Line Items]
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss	$ 0	$ 0

Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

+ Details

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

+ Details

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- Definition

Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

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