Derivative Instruments - Hedged Items in Fair Value Hedging Relationships (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Hedged Liability Statement Of Financial Position Extensible Enumeration Not Disclosed Flag	Carrying Amount Assets (Liabilities)	Carrying Amount Assets (Liabilities)
Hedged Asset Statement Of Financial Position Extensible Enumeration Not Disclosed Flag	Carrying Amount Assets (Liabilities)	Carrying Amount Assets (Liabilities)
Hedged asset, carrying amount	$ 1,343,231	$ 1,109,445
Hedged asset, total basis adjustments	(344)	(816)
Hedged asset, discontinued fair value, remaining adjustments	(344)	(816)
Closed portfolio, amortized cost	251,659	813,536
Closed portfolio, designated UPB	39,605	26,825
Hedged liability, carrying amount	(28,764)	(47,849)
Hedged liability, total basis adjustments	2,355	3,390
Hedged liability, discontinued fair value, remaining adjustments	$ 2,355	$ 3,390

Hedged Asset Statement Of Financial Position Extensible Enumeration Not Disclosed Flag

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Hedged Liability Statement Of Financial Position Extensible Enumeration Not Disclosed Flag

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- Definition

Amortized cost of closed portfolio of financial asset and beneficial interest secured by financial instrument, used to designate hedging relationship in which hedged item is expected to be outstanding for designated hedge period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EEE
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EEE

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
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-Paragraph 181
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-Publisher FASB
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Amount of asset hedged in fair value hedging relationship.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
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-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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Amount of asset hedged in portfolio layer hedging relationship, expected to be remaining at end of hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk.

+ References

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Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4EE
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-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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