Non-U.S. Activities - Schedule Of Results From Non-U.S. Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Total revenue	$ 2,903	$ 2,989	$ 8,708	$ 9,108
Income before income taxes	721	893	2,074	2,572
Non-U.S.
Segment Reporting Information [Line Items]
Total revenue	1,254	1,286	3,733	3,928
Income before income taxes	344	405	911	1,031
U.S.
Segment Reporting Information [Line Items]
Total revenue	1,649	1,703	4,975	5,180
Income before income taxes	$ 377	$ 488	$ 1,163	$ 1,541