Derivatives and Hedging Activities - Fair Values, Volume of Activity and Gain (Loss) Information Related to Derivative Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Notional Amount	$ 143,121	$ 148,690
Derivative assets, fair value	999	1,781
Derivative assets, netting adjustments	(818)	(757)
Derivative assets, fair value	180	1,024
Derivative liabilities, fair value	1,777	2,750
Derivative liabilities, netting adjustments	(473)	(1,262)
Derivative liabilities, fair value	1,286	1,483
Amount of offset in excess of collateral posted	161
Amount of offset in excess of securities collateral posted	269
Amount of offset in excess of cash collateral held	16
Amount of offset in excess of securities collateral held	212
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	98,500	107,490
Derivative assets, fair value	960	1,667
Derivative liabilities, fair value	1,765	2,747
Interest rate \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	44,621	41,200
Derivative assets, fair value	39	114
Derivative liabilities, fair value	12	3
Interest rate \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	78,051	80,772
Derivative assets, fair value	134	189
Derivative liabilities, fair value	973	1,304
Foreign exchange \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	6,034	9,507
Derivative assets, fair value	89	136
Derivative liabilities, fair value	73	131
Commodity \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	11,611	16,176
Derivative assets, fair value	721	1,328
Derivative liabilities, fair value	698	1,304
Credit \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	121	95
Derivative assets, fair value	0	1
Derivative liabilities, fair value	1	3
Other \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional Amount	2,683	940
Derivative assets, fair value	16	13
Derivative liabilities, fair value	20	5
Net derivatives in the balance sheet
Derivatives, Fair Value [Line Items]
Notional Amount	143,121	148,690
Derivative assets, fair value	181	1,024
Derivative liabilities, fair value	1,304	1,488
Other collateral
Derivatives, Fair Value [Line Items]
Derivative assets, fair value	(1)	0
Derivative liabilities, fair value	$ (18)	$ (5)

Derivative Instrument, Subject To Master Netting Arrangement, Collateral, Offset, Excess Collateral Held

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Derivative Instrument, Subject To Master Netting Arrangement, Collateral, Offset, Excess Collateral Posted

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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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Fair value, before effects of master netting arrangements, of a 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. Includes liabilities elected not to be offset. Excludes liabilities 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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Nominal or face amount used to calculate payment on derivative.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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