Share Repurchases - Additional Information (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended			3 Months Ended	12 Months Ended
	Sep. 30, 2019	Jan. 31, 2019	Nov. 30, 2017	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 01, 2017
Accelerated Share Repurchases [Line Items]
Stock repurchase program, authorized amount								$ 500.0
Open market share repurchase	$ 150.0	$ 100.0
Stock purchases, shares				4.1
Payment for share repurchase				$ 200.0	$ 250.0	$ 200.0	$ 400.0
Evergreen Program
Accelerated Share Repurchases [Line Items]
Payment for share repurchase	50.0			110.0
Repurchase Program
Accelerated Share Repurchases [Line Items]
Open market share repurchase			$ 100.0
Payment for share repurchase	$ 100.0			$ 90.0
Remaining amount for share repurchase program					$ 210.0