Financial Derivatives (Derivative Assets and Liabilities Offsetting) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	$ 3,220	$ 3,768
Derivative Asset, Fair Value Offset Amount	1,303	1,523
Derivative asset, cash collateral	1,134	714
Derivative Asset, Net	783	1,531
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	75	34
Derivative Asset, Fair Value, Amount Offset Against Collateral	708	1,497
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	7,003	7,618
Derivative liability, fair value offset amount	1,303	1,523
Derivative liability, cash collateral	1,135	1,571
Derivative liability, net	4,565	4,524
Derivative liability, fair value of collateral	75	82
Derivative liability, fair value, amount offset against collateral	4,490	4,442
Interest Rate Contracts | Over-the-counter cleared
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	26	23
Derivative Asset, Net	26	23
Derivative Asset, Fair Value, Amount Offset Against Collateral	26	23
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	19	28
Derivative liability, net	19	28
Derivative liability, fair value, amount offset against collateral	19	28
Interest Rate Contracts | Over-the-counter
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	2,230	2,100
Derivative Asset, Fair Value Offset Amount	846	974
Derivative asset, cash collateral	911	630
Derivative Asset, Net	473	496
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	75	34
Derivative Asset, Fair Value, Amount Offset Against Collateral	398	462
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	5,858	5,801
Derivative liability, fair value offset amount	633	625
Derivative liability, cash collateral	1,104	1,041
Derivative liability, net	4,121	4,135
Derivative liability, fair value of collateral	75	78
Derivative liability, fair value, amount offset against collateral	4,046	4,057
Commodity contracts:
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	622	1,208
Derivative Asset, Fair Value Offset Amount	337	335
Derivative asset, cash collateral	104	2
Derivative Asset, Net	181	871
Derivative Asset, Fair Value, Amount Offset Against Collateral	181	871
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	649	1,269
Derivative liability, fair value offset amount	497	679
Derivative liability, cash collateral	23	520
Derivative liability, net	129	70
Derivative liability, fair value of collateral		4
Derivative liability, fair value, amount offset against collateral	129	66
Foreign exchange contracts and other
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	342	437
Derivative Asset, Fair Value Offset Amount	120	214
Derivative asset, cash collateral	119	82
Derivative Asset, Net	103	141
Derivative Asset, Fair Value, Amount Offset Against Collateral	103	141
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	477	520
Derivative liability, fair value offset amount	173	219
Derivative liability, cash collateral	8	10
Derivative liability, net	296	291
Derivative liability, fair value, amount offset against collateral	$ 296	$ 291