Capital (Mandatorily Redeemable Capital Stock) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Mandatorily Redeemable Capital Stock [Roll Forward]
Balance at the beginning of the period	$ 48	$ 131	$ 106	$ 331
Payments for repurchase/redemption of mandatorily redeemable capital stock	(28)	(36)	(130)	(236)
Balance at the end of the period	20	112	20	112
Transfers of capital stock to mandatorily redeemable capital stock	$ 0	$ 17	$ 44	$ 17

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Value of net shares reclassified to mandatorily redeemable capital stock.

+ References

+ Details

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- Definition

The cash outflow related to equity securities that embody an unconditional obligation requiring the issuer to redeem the securities by transferring the assets at a specified or determinable date (or dates) that is (or are) initially more than one year (or the normal operating cycle, if longer) from the issuance date, or upon an event that is certain to occur beyond one year (or the normal operating cycle, if longer) from the issuance date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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- Definition

Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481648/480-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 64
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481620/480-10-55-64

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481679/480-10-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481648/480-10-50-2

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