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	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	$ 53	$ 105	$ (442)
Gain (loss) on derivative recognized in OCI, net investment hedge	540	(89)	291
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative	593	16	(151)
Gain (loss) on hedges reclassified to income, cash flow hedge	54	(208)	49
Gain (loss) on hedges reclassified to income, net investment hedge	0	0	0
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income	$ 54	(208)	49
Maximum maturity date of the underlying hedged items	5 years
Foreign exchange contracts
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	$ 59	91	156
Gain (loss) on derivative recognized in OCI, net investment hedge	540	(89)	291
Foreign exchange contracts \| Net interest revenue
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	254	2	92
Foreign exchange contracts \| Gains (Losses) related to investment securities, net
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, net investment hedge	0	0	0
Interest rate contracts
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	(6)	14	(598)
Interest rate contracts \| Net interest revenue
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	$ (200)	$ (210)	$ (43)

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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-Topic 220
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