Consolidated Obligations (Consolidated Obligation Bonds by Earlier of Contractual Maturity or Next Call Date) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule of Short-term and Long-term Debt [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	$ 30,135,080	$ 50,306,900
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	4,160,445	7,268,705
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Three	1,805,650	2,705,420
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Four	1,257,825	1,469,400
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Five	1,107,625	947,375
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	2,991,275	4,006,400
Long-term Debt, Gross	41,457,900	66,704,200
Earlier of Contractual Maturity or Next Call Date [Member] [Member]
Schedule of Short-term and Long-term Debt [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	32,028,080	54,157,900
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	4,171,445	6,573,705
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Three	1,793,650	2,623,420
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Four	1,142,825	1,063,400
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Five	812,625	827,375
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	$ 1,509,275	$ 1,458,400

Schedule of Short-term and Long-term Debt [Line Items]

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-SubTopic 210
-Section S99
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-SubTopic 10
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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