Derivatives and Hedging Activities - Fair Values, Volume of Activity and Gain (Loss) Information Related to Derivative Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Notional Amount	$ 137,761	$ 136,020
Derivative assets, Netting adjustments	(284)	(380)
Derivative assets, Fair Value	1,961	1,796
Derivative liabilities, Netting adjustments	(1,526)	(675)
Derivative liabilities, Fair Value	161	140
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	99,107	99,885
Derivative assets, Fair Value	2,207	2,108
Derivative liabilities, Fair Value	1,683	829
Interest rate \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	38,654	36,135
Derivative assets, Fair Value	39	70
Derivative liabilities, Fair Value	4	(3)
Interest rate \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	72,088	78,424
Derivative assets, Fair Value	768	1,514
Derivative liabilities, Fair Value	249	291
Foreign exchange \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	9,073	6,385
Derivative assets, Fair Value	81	109
Derivative liabilities, Fair Value	76	103
Commodity \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	14,151	9,702
Derivative assets, Fair Value	1,330	426
Derivative liabilities, Fair Value	1,335	408
Credit \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	465	423
Derivative assets, Fair Value	1	1
Derivative liabilities, Fair Value	12	11
Other \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	3,330	4,951
Derivative assets, Fair Value	27	58
Derivative liabilities, Fair Value	11	16
Net derivatives in the balance sheet
Derivatives, Fair Value [Line Items]
Notional Amount	137,761	136,020
Derivative assets, Fair Value	1,962	1,798
Derivative liabilities, Fair Value	161	151
Other collateral
Derivatives, Fair Value [Line Items]
Derivative assets, Fair Value	(1)	(2)
Derivative liabilities, Fair Value	$ 0	$ (11)

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

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