Derivative Instruments - Customer-Related Derivative Positions (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Notional Value	$ 1,200,000
Customer-Related Positions
Derivative [Line Items]
Notional Value	1,114,066	$ 1,119,842
Fair Value, Assets	5,781	6,219
Fair Value, Liabilities	8,566	8,068
Customer-Related Positions | Interest rate contracts | Receive fixed/pay floating swaps
Derivative [Line Items]
Notional Value	369,671	363,375
Fair Value, Assets	439	791
Fair Value, Liabilities	5,184	4,395
Customer-Related Positions | Interest rate contracts | Pay fixed/receive floating swaps
Derivative [Line Items]
Notional Value	345,929	330,539
Fair Value, Assets	2,147	1,817
Fair Value, Liabilities	170	280
Customer-Related Positions | Interest rate contracts | Other
Derivative [Line Items]
Notional Value	76,713	82,209
Fair Value, Assets	15	17
Fair Value, Liabilities	50	51
Customer-Related Positions | Interest rate contracts | Options | Buy/ Purchased
Derivative [Line Items]
Notional Value	95,653	102,423
Fair Value, Assets	736	1,026
Fair Value, Liabilities	1	18
Customer-Related Positions | Interest rate contracts | Options | Sell/ Written
Derivative [Line Items]
Notional Value	91,365	97,690
Fair Value, Assets	9	20
Fair Value, Liabilities	953	1,087
Customer-Related Positions | Foreign exchange rate contracts | Forwards, spots and swaps
Derivative [Line Items]
Notional Value	109,853	121,119
Fair Value, Assets	2,054	2,252
Fair Value, Liabilities	1,836	1,942
Customer-Related Positions | Foreign exchange options | Buy/ Purchased
Derivative [Line Items]
Notional Value	538	1,532
Fair Value, Assets	17	28
Fair Value, Liabilities	0	0
Customer-Related Positions | Foreign exchange options | Sell/ Written
Derivative [Line Items]
Notional Value	538	1,532
Fair Value, Assets	0	0
Fair Value, Liabilities	17	28
Customer-Related Positions | Commodity contracts | Swaps
Derivative [Line Items]
Notional Value	5,010	2,498
Fair Value, Assets	140	116
Fair Value, Liabilities	135	110
Customer-Related Positions | Commodity contracts | Futures | Sell/ Written
Derivative [Line Items]
Notional Value	83	0
Fair Value, Assets	17	0
Fair Value, Liabilities	10	0
Customer-Related Positions | Commodity options | Buy/ Purchased
Derivative [Line Items]
Notional Value	3,080	1,936
Fair Value, Assets	205	151
Fair Value, Liabilities	1	0
Customer-Related Positions | Commodity options | Sell/ Written
Derivative [Line Items]
Notional Value	3,079	1,936
Fair Value, Assets	1	0
Fair Value, Liabilities	205	151
Customer-Related Positions | Credit contracts
Derivative [Line Items]
Notional Value	12,554	13,053
Fair Value, Assets	1	1
Fair Value, Liabilities	$ 4	$ 6