Consolidated Obligations Contractual Maturity or Next Call Date (Details) - Unsecured Debt [Member] - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Consolidated Obligations by Contractual Maturity or Next Call Date [Line Items]
Debt, Gross	$ 60,660,575	$ 58,340,975
Earlier of Contractual Maturity or Next Call Date [Member]
Consolidated Obligations by Contractual Maturity or Next Call Date [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	55,011,810	52,120,085
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	3,039,050	3,773,330
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Three	1,622,585	1,464,430
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Four	726,130	777,130
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Five	216,000	161,000
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	45,000	45,000
Debt, Gross	$ 60,660,575	$ 58,340,975

[Line Items] for Consolidated Obligations by Contractual Maturity or Next Call Date [Table]

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Including current and noncurrent portions, aggregate carrying principal amount of borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any).

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

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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 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 fourth 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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- Definition

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 third 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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