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, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	$ 13	$ 154	$ 51
Gain (loss) on derivative recognized in OCI, net investment hedge	272	(250)	30
Amount of Gain or (Loss) Recognized in Other Comprehensive Income on Derivative	285	(96)	81
Gain (loss) on hedges reclassified to income, cash flow hedge	95	72	17
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	95	72	17
Foreign exchange contracts
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	91	(22)	43
Gain (loss) on derivative recognized in OCI, net investment hedge	272	(250)	30
Foreign exchange contracts \| Net interest revenue
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	11	23	27
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	(78)	176	8
Interest rate contracts \| Net interest revenue
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	$ 84	$ 49	$ (10)

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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
-Publisher FASB
-Name Accounting Standards Codification
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