Non-U.S. Activities - Schedule Of Results From Non-U.S. Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Total revenue	$ 2,951	$ 2,846	$ 8,996	$ 8,324
Income before income taxes	867	822	2,495	2,182
Non-U.S.
Segment Reporting Information [Line Items]
Total revenue	1,286	1,219	3,929	3,494
Income before income taxes	497	342	1,343	919
U.S.
Segment Reporting Information [Line Items]
Total revenue	1,665	1,627	5,067	4,830
Income before income taxes	$ 370	$ 480	$ 1,152	$ 1,263