Other Intangible Assets - Schedule of Amortization Expense (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ (6.8)	$ (6.9)	$ (20.4)	$ (20.6)
Product Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			(2.8)	(2.8)
Brand Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			(0.9)	(0.9)
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			(2.5)	(2.5)
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			(8.0)	(7.6)
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			0.0	(0.6)
Marketing Related [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			0.0	(0.7)
Internally Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization expense			$ (6.2)	$ (5.5)