Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Shareholders’ net income	$ 1,181	$ 1,368
Shares:
Weighted average (in shares)	370,440	379,387
Common stock equivalents (in shares)	4,199	4,637
Total shares (in shares)	374,639	384,024
EPS, basic (in dollars per share)	$ 3.19	$ 3.61
EPS, effect of dilution (in dollars per share)	(0.04)	(0.05)
EPS, diluted (in dollars per share)	$ 3.15	$ 3.56