Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income tax expense:
U.S. federal	$ 1,108	$ 70	$ 3,408
U.S. state and local	276	150	259
Non-U.S.	437	681	387
Total current income tax expense	1,821	901	4,054
Deferred income tax expense (benefit):
U.S. federal	(58)	276	544
U.S. state and local	(31)	78	(12)
Non-U.S.	(62)	(54)	91
Total deferred income tax expense	(151)	300	623
Income tax provision (benefit)	$ 1,670	$ 1,201	$ 4,677