Derivatives and Hedging Activities - Schedule of Fair Values, Volume of Activity and Gain (Loss) Information Related to Derivative Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Notional Amount	$ 149,589	$ 143,121
Derivative assets, netting adjustments	(499)	(818)
Derivative Assets, net	191	180
Derivative liabilities, netting adjustments	(343)	(473)
Derivative Liabilities, net	838	1,286
Amount of offset in excess of collateral posted	170	161
Amount of offset in excess of securities collateral posted	261	269
Amount of offset in excess of cash collateral held	30	16
Amount of offset in excess of securities collateral held	188	212
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	91,082	98,500
Derivative Assets	698	960
Derivative Liabilities	1,163	1,765
Interest rate \| Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	58,507	44,621
Derivative Assets	(8)	39
Derivative Liabilities	20	12
Interest rate \| Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	72,584	78,051
Derivative Assets	194	134
Derivative Liabilities	675	973
Foreign exchange \| Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	6,383	6,034
Derivative Assets	70	89
Derivative Liabilities	63	73
Commodity \| Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	8,832	11,611
Derivative Assets	423	721
Derivative Liabilities	401	698
Credit \| Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	136	121
Derivative Assets	0	0
Derivative Liabilities	17	1
Other \| Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional Amount	3,147	2,683
Derivative Assets	11	16
Derivative Liabilities	7	20
Net derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	149,589	143,121
Derivative Assets, net	191	181
Derivative Liabilities, net	840	1,304
Other collateral
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Derivative Assets, net	0	(1)
Derivative Liabilities, net	$ (2)	$ (18)

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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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