Derivatives and Hedging Activities - Derivative Instrument Cash Flow Hedge Earning Recognized by Income Statement Location (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Net Gains (Losses) Recognized in OCI	$ (295)	$ 614	$ 440
Net Gains (Losses) Reclassified From OCI Into Income	329	315	46
Net Gains (Losses) Recognized in Other Income	0	0	0
Interest income — Loans \| Interest rate \| Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Net Gains (Losses) Recognized in OCI	(307)	628	442
Net Gains (Losses) Reclassified From OCI Into Income	329	319	15
Net Gains (Losses) Recognized in Other Income	0	0	0
Interest expense — Long-term debt \| Interest rate \| Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Net Gains (Losses) Recognized in OCI	2	(5)	(1)
Net Gains (Losses) Reclassified From OCI Into Income	(4)	(4)	(1)
Net Gains (Losses) Recognized in Other Income	0	0	0
Investment banking and debt placement fees \| Interest rate \| Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Net Gains (Losses) Recognized in OCI	10	(9)	3
Net Gains (Losses) Reclassified From OCI Into Income	4	0	0
Net Gains (Losses) Recognized in Other Income	0	0	0
Other income \| Foreign exchange \| Net Investment Hedges
Derivatives, Fair Value [Line Items]
Net Gains (Losses) Recognized in OCI	0	0	(4)
Net Gains (Losses) Reclassified From OCI Into Income	0	0	32
Net Gains (Losses) Recognized in Other Income	$ 0	$ 0	$ 0

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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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

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Amount, after 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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