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, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	$ 105	$ (442)	$ 13
Gain (loss) on derivative recognized in OCI, net investment hedge	(89)	291	272
Amount of Gain or (Loss) Recognized in Other Comprehensive Income on Derivative	16	(151)	285
Gain (loss) on hedges reclassified to income, cash flow hedge	(208)	49	95
Gain (loss) on hedges reclassified to income, net investment hedge	0	0	0
Amount of Gain or (Loss) Reclassified from Accumulated Other Comprehensive Income into Income	(208)	49	95
Foreign exchange contracts
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	91	156	91
Gain (loss) on derivative recognized in OCI, net investment hedge	(89)	291	272
Foreign exchange contracts \| Net interest revenue
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	2	92	11
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	14	(598)	(78)
Interest rate contracts \| Net interest revenue
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	$ (210)	$ (43)	$ 84

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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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/disclosureRef
-Topic 220
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