Divestitures and Planned Divestitures - Summary of Amounts Included in Discontinued Operations (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Discontinued Operations and Disposal Groups [Abstract]
Net sales		$ 56.5
Loss from discontinued operations before income taxes	$ (1.9)	(7.7)
Income tax benefit	(0.6)	(2.8)
Loss from discontinued operations	(1.3)	(4.9)
Net gain from sale of discontinued operations, net of tax	0.6	95.6
Income (loss) from discontinued operations, net of tax	$ (0.7)	$ 90.7