Summary of Option Activity (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Beginning Balance, Options | shares	14.0
Granted, Options | shares	1.9
Exercised, Options | shares	(3.1)
Cancelled, Options | shares	(0.1)
Ending Balance, Options | shares	12.7
Exercisable as of December 31, 2020, Options | shares	7.6
Beginning Balance, Weighted-Average Exercise Price | $ / shares	$ 43.23
Granted, Weighted-Average Exercise Price | $ / shares	74.39
Exercised, Weighted-Average Exercise Price | $ / shares	30.23
Cancelled, Weighted-Average Exercise Price | $ / shares	65.44
Ending Balance, Weighted-Average Exercise Price | $ / shares	50.72
Exercisable as of December 31, 2020, Weighted-Average Exercise Price | $ / shares	$ 39.92
Outstanding as of December 31, 2020, Weighted-Average Remaining Contractual Term, years	5 years 9 months 18 days
Exercisable as of December 31, 2020, Weighted-Average Remaining Contractual Term, years	4 years
Outstanding as of December 31, 2020, Aggregate Intrinsic Value | $	$ 463.4
Exercisable as of December 31, 2020, Aggregate Intrinsic Value | $	$ 357.7