Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Millions		3 Months Ended
	Aug. 04, 2016	Mar. 31, 2017 USD ($) $ / shares	Mar. 31, 2016 USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Common stock split ratio	2
Stock dividend payable percentage of common stock	100.00%
Stock dividend payable date		Sep. 01, 2016
Stock dividend record date		Aug. 15, 2016
Excess tax benefit from operating activities		$ 0.0	$ 7.9
Excess tax benefit from financing activities		0.0	7.9
Research and development expenses		14.1	$ 14.4
ASU 2016-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Excess tax benefit from operating activities		$ 8.7
Excess tax benefit per share from operating activities | $ / shares		$ 0.03
Excess tax benefit from financing activities		$ 8.7
Excess tax benefit per share from financing activities | $ / shares		$ 0.03