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, 2025	Dec. 31, 2024
Derivatives, Fair Value [Line Items]
Notional Amount	$ 155,868	$ 155,415
Derivative Assets	559	612
Derivative assets, netting adjustments	(329)	(363)
Derivative Assets, net	227	249
Derivative Liabilities	971	1,439
Derivative liabilities, netting adjustments	(334)	(411)
Derivative Liabilities, net	636	1,027
Amount of offset in excess of collateral posted	175	168
Amount of offset in excess of securities collateral posted	207	215
Amount of offset in excess of cash collateral held	8	13
Amount of offset in excess of securities collateral held	114	32
Hedge accounting basis adjustment - discontinued hedges
Derivatives, Fair Value [Line Items]
Notional Amount	92,818	90,714
Derivative Assets	542	616
Derivative Liabilities	971	1,436
Interest rate \| Hedge accounting basis adjustment - active hedges
Derivatives, Fair Value [Line Items]
Notional Amount	63,050	64,701
Derivative Assets	17	(4)
Derivative Liabilities	0	3
Interest rate \| Hedge accounting basis adjustment - discontinued hedges
Derivatives, Fair Value [Line Items]
Notional Amount	74,725	72,215
Derivative Assets	147	114
Derivative Liabilities	574	962
Foreign exchange \| Hedge accounting basis adjustment - discontinued hedges
Derivatives, Fair Value [Line Items]
Notional Amount	5,809	6,516
Derivative Assets	102	124
Derivative Liabilities	96	117
Commodity \| Hedge accounting basis adjustment - discontinued hedges
Derivatives, Fair Value [Line Items]
Notional Amount	6,083	8,778
Derivative Assets	276	363
Derivative Liabilities	263	343
Credit \| Hedge accounting basis adjustment - discontinued hedges
Derivatives, Fair Value [Line Items]
Notional Amount	78	60
Derivative Assets	0	0
Derivative Liabilities	8	0
Other \| Hedge accounting basis adjustment - discontinued hedges
Derivatives, Fair Value [Line Items]
Notional Amount	6,123	3,145
Derivative Assets	17	15
Derivative Liabilities	30	14
Net derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	155,868	155,415
Derivative Assets, net	230	249
Derivative Liabilities, net	637	1,028
Other collateral
Derivatives, Fair Value [Line Items]
Notional Amount	0	0
Derivative Assets, net	(3)	0
Derivative Liabilities, net	$ (1)	$ (1)

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