Derivative Instruments - Customer-Related Derivative Positions (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Derivative [Line Items]
Notional Value	$ 1,300,000
Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	107,542	$ 105,692
Fair Value, Assets	298	275
Fair Value, Liabilities	191	221
Customer-Related Positions
Derivative [Line Items]
Notional Value	1,191,653	1,181,606
Fair Value, Assets	5,652	6,162
Fair Value, Liabilities	6,572	7,939
Customer-Related Positions | Interest rate contracts | Receive fixed/pay floating swaps
Derivative [Line Items]
Notional Value	404,356	413,841
Fair Value, Assets	877	462
Fair Value, Liabilities	3,260	4,485
Customer-Related Positions | Interest rate contracts | Pay fixed/receive floating swaps
Derivative [Line Items]
Notional Value	364,577	363,837
Fair Value, Assets	1,703	2,342
Fair Value, Liabilities	279	153
Customer-Related Positions | Interest rate contracts | Other
Derivative [Line Items]
Notional Value	70,207	72,503
Fair Value, Assets	17	17
Fair Value, Liabilities	32	34
Customer-Related Positions | Interest rate contracts | Options | Buy/ Purchased
Derivative [Line Items]
Notional Value	105,399	96,238
Fair Value, Assets	366	414
Fair Value, Liabilities	6	2
Customer-Related Positions | Interest rate contracts | Options | Sell/ Written
Derivative [Line Items]
Notional Value	90,579	90,572
Fair Value, Assets	18	12
Fair Value, Liabilities	488	574
Customer-Related Positions | Interest rate contracts | Futures | Buy/ Purchased
Derivative [Line Items]
Notional Value	1,240	0
Fair Value, Assets	0	0
Fair Value, Liabilities	0	0
Customer-Related Positions | Interest rate contracts | Futures | Sell/ Written
Derivative [Line Items]
Notional Value	301	0
Fair Value, Assets	0	0
Fair Value, Liabilities	0	0
Customer-Related Positions | Foreign exchange rate contracts | Forwards, spots and swaps
Derivative [Line Items]
Notional Value	119,520	113,718
Fair Value, Assets	1,932	2,441
Fair Value, Liabilities	1,789	2,232
Customer-Related Positions | Foreign exchange options | Buy/ Purchased
Derivative [Line Items]
Notional Value	790	497
Fair Value, Assets	15	14
Fair Value, Liabilities	1	0
Customer-Related Positions | Foreign exchange options | Sell/ Written
Derivative [Line Items]
Notional Value	790	497
Fair Value, Assets	1	0
Fair Value, Liabilities	15	14
Customer-Related Positions | Commodity contracts | Swaps
Derivative [Line Items]
Notional Value	10,972	8,224
Fair Value, Assets	362	199
Fair Value, Liabilities	301	180
Customer-Related Positions | Commodity contracts | Futures | Buy/ Purchased
Derivative [Line Items]
Notional Value	1	1
Fair Value, Assets	0	0
Fair Value, Liabilities	0	0
Customer-Related Positions | Commodity contracts | Futures | Sell/ Written
Derivative [Line Items]
Notional Value	249	166
Fair Value, Assets	49	25
Fair Value, Liabilities	84	27
Customer-Related Positions | Commodity options | Buy/ Purchased
Derivative [Line Items]
Notional Value	4,953	3,921
Fair Value, Assets	310	233
Fair Value, Liabilities	4	2
Customer-Related Positions | Commodity options | Sell/ Written
Derivative [Line Items]
Notional Value	4,953	3,921
Fair Value, Assets	2	3
Fair Value, Liabilities	310	233
Customer-Related Positions | Credit contracts
Derivative [Line Items]
Notional Value	12,758	13,670
Fair Value, Assets	0	0
Fair Value, Liabilities	3	3
Other economic hedges | Interest rate contracts | Receive fixed/pay floating swaps | Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	10,443	9,977
Fair Value, Assets	78	45
Fair Value, Liabilities	30	23
Other economic hedges | Interest rate contracts | Pay fixed/receive floating swaps | Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	2,818	2,371
Fair Value, Assets	0	0
Fair Value, Liabilities	0	0
Other economic hedges | Interest rate contracts | Options | Buy/ Purchased | Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	6,724	7,810
Fair Value, Assets	176	186
Fair Value, Liabilities	0	0
Other economic hedges | Interest rate contracts | Options | Sell/ Written | Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	2,672	1,991
Fair Value, Assets	17	8
Fair Value, Liabilities	54	47
Other economic hedges | Credit contracts | Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	3,298	3,558
Fair Value, Assets	6	0
Fair Value, Liabilities	17	29
Other economic hedges | Equity contracts
Derivative [Line Items]
Notional Value	8	0
Fair Value, Assets	0	0
Fair Value, Liabilities	0	0
Other economic hedges | Equity contracts | Asset and Liability Management Positions
Derivative [Line Items]
Notional Value	288	293
Fair Value, Assets	0	0
Fair Value, Liabilities	$ 6	$ 9