Business Disposition - Schedule of Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Total	$ 0.4	$ 38.0
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)	(0.4)	19.8
After-tax gain on disposal	0.4	38.6
Total	$ 0.4	38.0
Net cash provided by operating activities		2.3
Net cash used in investing activities		$ (0.1)

Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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