Consolidated Obligations (Discount Notes) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Short-term Debt [Line Items]
Short-term Debt, Weighted Average Interest Rate, at Point in Time	1.65%	2.34%
Debt Instrument, Unamortized Discount	$ (38)	$ (48)
Total	29,531	42,879
Short-term Debt [Member]
Short-term Debt [Line Items]
Debt Instrument, Face Amount	29,592	43,052
Debt Instrument, Unamortized Discount	$ (61)	$ (173)

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of joint and several obligations consisting of discount notes issued by Federal Home Loan Banks (FHLBanks).

+ References

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.

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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