Stock-Based Compensation - Summary of Changes in SARs Outstanding (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Weighted Average Remaining Contractual Term (Years)
Granted	2 years 3 months 18 days
Stock appreciation rights
SARs
Outstanding, Beginning Balance (in shares)	1.2
Granted (in shares)	0.3
Forfeited (in shares)	(0.1)
Exercised (in shares)	(0.2)
Outstanding, Ending Balance (in shares)	1.2	1.2
Vested and exercisable, ending balance (in shares)	0.5
Per Share Weighted Average Exercise Price
Outstanding, Beginning Balance (in dollars per share)	$ 89.45
Granted (in dollars per share)	143.23
Forfeited (in dollars per share)	118.31
Exercised (in dollars per share)	73.64
Outstanding, Ending Balance (in dollars per share)	104.05	$ 89.45
Vested and exercisable, ending balance (in Dollars per share)			$ 85.79
Per Share Weighted Average Grant Date Fair Value
Outstanding, Beginning Balance (in dollars per share)	19.88
Granted (in dollars per share)	32.62
Forfeited (in dollars per share)	26.52
Exercised (in Dollars per share)	16.92
Outstanding, Ending Balance (in dollars per share)	$ 23.18	$ 19.88
Vested and exercisable, ending balance (in Dollars per share)			$ 18.87
Weighted Average Remaining Contractual Term (Years)
Weighted average remaining contractual terms	4 years 2 months 15 days	4 years 3 months 29 days
Granted	6 years 1 month 9 days
Weighted average remaining contractual terms vested and exercisable	3 years 1 month 17 days
Unvested SARs (in shares)	1.2	1.2	1.2
Aggregate intrinsic value of outstanding shares			$ 58.9
Aggregate intrinsic value of shares vested and exercisable			$ 37.1
Stock appreciation rights | Unvested
SARs
Outstanding, Ending Balance (in shares)	0.7
Weighted Average Remaining Contractual Term (Years)
Unvested SARs (in shares)	0.7		0.7