Derivative Financial Instruments - Schedule of Differences Between the Gains (Losses) on the Derivative and the Gains (Losses) on the Hedged Item (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Derivative [Line Items]
Total derivatives designated as cash flow hedges	$ (14)	$ 15	$ (2)	$ 53
Total derivatives designated as net investment hedges	86	(265)	(821)	(22)
Amount of Gain or (Loss) Recognized in Other Comprehensive Income on Derivative	72	(250)	(823)	31
Total derivatives designated as cash flow hedges	(34)	(51)	(107)	94
Total derivatives designated as net investment hedges	0	0	0	0
Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income into Income	(34)	(51)	(107)	94
Interest rate contracts
Derivative [Line Items]
Total derivatives designated as cash flow hedges	(14)	15	$ (2)	(6)
Term of debt instrument			5 years
Interest rate contracts \| Net interest income
Derivative [Line Items]
Total derivatives designated as cash flow hedges	(34)	(51)	$ (107)	(160)
Foreign exchange contracts
Derivative [Line Items]
Total derivatives designated as cash flow hedges			0	59
Total derivatives designated as net investment hedges	86	(265)	(821)	(22)
Total derivatives designated as net investment hedges	$ 0	$ 0	0	0
Foreign exchange contracts \| Net interest income
Derivative [Line Items]
Total derivatives designated as cash flow hedges			$ 0	$ 254

Other Comprehensive Income (Loss), Derivative, Before Reclassification And Tax

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 182
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-182

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from derivative designated and qualifying as net investment hedge.

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