Derivative Financial Instruments and Hedging Activities - Schedule of Balance Sheet (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Derivatives, Fair Value [Line Items]
Hedged Liability, Statement of Financial Position [Extensible Enumeration]	Unsecured debt (Note 6)	Unsecured debt (Note 6)
Derivatives designated as hedges \| Fair value hedges
Derivatives, Fair Value [Line Items]
Carrying Amount of Hedged Items	$ 37,684	$ 36,664
Cumulative Amount of Fair Value Hedging Adjustments	960	1,281
Discontinued hedge cumulative amount of fair value hedging adjustments	$ 669	$ 719

Derivative Liability, Fair Value Hedging Adjustment Increase (Decrease)

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- Definition

Derivative Liability, Fair Value Hedging Adjustment Increase (Decrease), Discontinuation Of Hedge Accounting

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE

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- Definition

Indicates line item in statement of financial position that includes hedged liability.

+ References

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

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