Share-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Summary of stock option activity, Shares
Outstanding, beginning (in shares)	4.8
Granted (in shares)	0.3
Exercised (in shares)	(1.8)
Outstanding, ending (in shares)	3.3	4.8
Exercisable (in shares)	2.2
Summary of stock option activity, Weighted Average Exercise Price
Outstanding (in dollars per share)	$ 145.79	$ 133.75
Granted (in dollars per share)	197.97
Exercised (in dollars per share)	123.30
Exercisable (in dollars per share)	$ 138.35
Summary of stock option activity, Weighted Average Remaining Contractual Term and Aggregate Intrinsic Value
Weighted Average Remaining Contractual Term, Outstanding	6 years 3 months 18 days	6 years 6 months
Weighted Average Remaining Contractual Term, Exercisable	5 years 6 months
Aggregate Intrinsic Value, Outstanding	$ 518	$ 290
Aggregate Intrinsic Value, Exercisable	365
Aggregate Intrinsic Value, Exercised	$ 219	$ 139	$ 61