Other Intangible Assets - Schedule of Amortization Expense (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ (6.7)	$ (6.9)
Product Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(0.9)	(0.9)
Brand Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(0.3)	(0.3)
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(0.9)	(0.9)
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	(2.6)	(2.6)
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	0.0	(0.2)
Marketing Related [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	0.0	(0.2)
Internally Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ (2.0)	$ (1.8)