Financial Derivatives (Derivative Assets and Liabilities Offsetting) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	$ 3,153	$ 3,768
Derivative Asset, Fair Value Offset Amount	1,518	1,523
Derivative asset, cash collateral	634	714
Derivative Asset, Net	1,001	1,531
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	45	34
Derivative Asset, Fair Value, Amount Offset Against Collateral	956	1,497
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	6,116	7,618
Derivative liability, fair value offset amount	1,518	1,523
Derivative liability, cash collateral	911	1,571
Derivative liability, net	3,687	4,524
Derivative liability, fair value of collateral	37	82
Derivative liability, fair value, amount offset against collateral	3,650	4,442
Interest Rate Contracts | Over-the-counter cleared
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	16	23
Derivative Asset, Net	16	23
Derivative Asset, Fair Value, Amount Offset Against Collateral	16	23
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	26	28
Derivative liability, net	26	28
Derivative liability, fair value, amount offset against collateral	26	28
Interest Rate Contracts | Over-the-counter
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	1,964	2,100
Derivative Asset, Fair Value Offset Amount	908	974
Derivative asset, cash collateral	445	630
Derivative Asset, Net	611	496
Derivative Asset, Securities Collateral Held Under Master Netting Agreements	45	34
Derivative Asset, Fair Value, Amount Offset Against Collateral	566	462
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	4,796	5,801
Derivative liability, fair value offset amount	764	625
Derivative liability, cash collateral	861	1,041
Derivative liability, net	3,171	4,135
Derivative liability, fair value of collateral	37	78
Derivative liability, fair value, amount offset against collateral	3,134	4,057
Commodity contracts:
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	769	1,208
Derivative Asset, Fair Value Offset Amount	411	335
Derivative asset, cash collateral	99	2
Derivative Asset, Net	259	871
Derivative Asset, Fair Value, Amount Offset Against Collateral	259	871
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	814	1,269
Derivative liability, fair value offset amount	558	679
Derivative liability, cash collateral	41	520
Derivative liability, net	215	70
Derivative liability, fair value of collateral		4
Derivative liability, fair value, amount offset against collateral	215	66
Foreign exchange contracts and other
Offsetting Derivative Assets [Abstract]
Derivative asset, gross fair value	404	437
Derivative Asset, Fair Value Offset Amount	199	214
Derivative asset, cash collateral	90	82
Derivative Asset, Net	115	141
Derivative Asset, Fair Value, Amount Offset Against Collateral	115	141
Offsetting Derivative Liabilities [Abstract]
Derivative liability, gross fair value	480	520
Derivative liability, fair value offset amount	196	219
Derivative liability, cash collateral	9	10
Derivative liability, net	275	291
Derivative liability, fair value, amount offset against collateral	$ 275	$ 291