Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Shareholders' net income	$ 5,365	$ 8,458	$ 5,104
Shares:
Weighted average (in shares)	337,962	364,979	375,919
Common stock equivalents (in shares)	3,004	3,410	3,898
Total shares (in shares)	340,966	368,389	379,817
EPS, basic (in dollars per share)	$ 15.87	$ 23.17	$ 13.58
EPS, effect of dilution (in dollars per share)	(0.14)	(0.21)	(0.14)
EPS, diluted (in dollars per share)	$ 15.73	$ 22.96	$ 13.44