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
Mar. 31, 2023	Mar. 31, 2022
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	$ 19	$ (244)
Gain (loss) on derivative recognized in OCI, net investment hedge	(41)	64
Other comprehensive income (loss), derivative, before reclassification and tax	(22)	(180)
Gain (loss) on hedges reclassified to income, cash flow hedge	(51)	22
Other comprehensive income (loss), derivative, gain (loss), reclassification, before tax	(51)	22
Gain (loss) on hedges reclassified to income, net investment hedge	$ 0	0
Floating-rate loans
Derivative [Line Items]
Term of debt instrument	5 years
Interest rate contracts
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	$ 3	(291)
Interest rate contracts \| Net interest income
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	(51)	19
Foreign exchange contracts
Derivative [Line Items]
Gain (loss) on derivative recognized in OCI, cash flow hedge	16	47
Gain (loss) on derivative recognized in OCI, net investment hedge	(41)	64
Foreign exchange contracts \| Net interest income
Derivative [Line Items]
Gain (loss) on hedges reclassified to income, cash flow hedge	0	3
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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 45
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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