Commitments and Contingencies - Rollforward of Environmental Liability and Related Assets (Detail) - Environmental Related Matters [Member] - Liability [Member] - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Environmental Liability and Related Assets [Roll Forward]
Environmental liability - Beginning balance		$ 82.6	$ 89.9
Net cash activity, Liability		(11.9)	(12.1)
Foreign currency, Liability		0.0	(0.6)
Environmental liability - Ending balance		76.6	82.6
Additions [Member]
Environmental Liability and Related Assets [Roll Forward]
Continuing operations, Liability	[1]	6.6	11.0
Reversal [Member]
Environmental Liability and Related Assets [Roll Forward]
Continuing operations, Liability		$ (0.7)	$ (5.6)

[1] (a)Changes in estimates for pre-existing accruals includes environmental-related costs of $0.7 and a reversal of prior accruals of $0.9 reported within results of discontinued operations for the years ended December 31, 2016 and 2015, respectively.