Financial Derivatives (Derivative Assets and Liabilities Offsetting) (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	$ 3,120	$ 3,429
Derivative Asset, Fair Value Offset Amount	1,321	1,406
Derivative asset, cash collateral	1,139	1,126
Derivative Asset, Net	660	897
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	33	66
Derivative Asset, Fair Value, Amount Offset Against Collateral	627	831
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	6,216	5,899
Derivative liability, fair value offset amount	1,321	1,406
Derivative liability, cash collateral	1,189	955
Derivative liability, net	3,706	3,538
Derivative liability, fair value of collateral	64	58
Derivative liability, fair value, amount offset against collateral	3,642	3,480
Interest Rate Contracts | Over-the-counter cleared
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	11	19
Derivative Asset, Net	11	19
Derivative Asset, Fair Value, Amount Offset Against Collateral	11	19
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	15	36
Derivative liability, net	15	36
Derivative liability, fair value, amount offset against collateral	15	36
Interest Rate Contracts | Over-the-counter
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	2,199	2,338
Derivative Asset, Fair Value Offset Amount	914	976
Derivative asset, cash collateral	870	767
Derivative Asset, Net	415	595
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	31	61
Derivative Asset, Fair Value, Amount Offset Against Collateral	384	534
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	5,226	4,612
Derivative liability, fair value offset amount	802	885
Derivative liability, cash collateral	1,188	942
Derivative liability, net	3,236	2,785
Derivative liability, fair value of collateral	64	58
Derivative liability, fair value, amount offset against collateral	3,172	2,727
Commodity contracts:
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	610	765
Derivative Asset, Fair Value Offset Amount	324	316
Derivative asset, cash collateral	156	283
Derivative Asset, Net	130	166
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	2	5
Derivative Asset, Fair Value, Amount Offset Against Collateral	128	161
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	586	757
Derivative liability, fair value offset amount	418	332
Derivative liability, cash collateral
Derivative liability, net	168	425
Derivative liability, fair value, amount offset against collateral	168	425
Foreign exchange contracts and other
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	300	307
Derivative Asset, Fair Value Offset Amount	83	114
Derivative asset, cash collateral	113	76
Derivative Asset, Net	104	117
Derivative Asset, Fair Value, Amount Offset Against Collateral	104	117
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	389	494
Derivative liability, fair value offset amount	101	189
Derivative liability, cash collateral	1	13
Derivative liability, net	287	292
Derivative liability, fair value, amount offset against collateral	$ 287	$ 292