Advances (Interest Rate Payment Terms) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Federal Home Loan Bank, Advances, Fixed Rate [Abstract]
Fixed rate – overnight	$ 711,891	$ 3,847,547
Due in 1 year or less	8,783,285	18,059,289
Thereafter	12,437,464	16,424,647
Total Fixed Rate	21,932,640	38,331,483
Federal Home Loan Bank, Advances, Floating Rate [Abstract]
Due in 1 year or less	12,671,843	19,354,536
Thereafter	878,100	7,753,100
Total Variable Rate	13,549,943	27,107,636
Total Par Value	$ 35,482,583	$ 65,439,119

Amount of Federal Home Loan Bank advances having fixed interest rates and overnight maturities.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesFixedRate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

Par amount of advance made and reported by Federal Home Loan Bank (FHLBank) with fixed interest rate maturing after next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesFixedRateAfterOneYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Par amount of advance made and reported by Federal Home Loan Bank (FHLBank) with fixed interest rate maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesFloatingRate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Par amount of advance made and reported by Federal Home Loan Bank (FHLBank) with floating interest rate maturing after next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Par amount of advance made and reported by Federal Home Loan Bank (FHLBank) with floating interest rate maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant