Business Disposition - Schedule of Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Total	$ 0.7	$ 38.7
Waste Management
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net sales		4.6
Operating loss		(0.4)
Interest expense, net		(0.3)
Loss before taxes		(0.7)
Income tax benefit		(0.1)
Net loss		(0.6)
Pre-tax gain on disposal		58.4
Income tax expense (benefit)	(0.7)	19.1
After-tax gain on disposal	0.7	39.3
Total	$ 0.7	38.7
Net cash provided by operating activities		2.3
Net cash used in investing activities		$ (0.1)