Restructuring and Relocation Activities - Restructuring Activities (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 12.1	$ 2.5	$ 48.7
Total	28.8	40.9	121.2
Capital expenditures	21.3	123.5	52.0
Continuing Operations
Restructuring Cost And Reserve [Line Items]
Other associated costs	14.3	19.8	25.7
Restructuring charges	12.1	2.5	48.7
Total	26.4	22.3	74.4
Discontinued Operations
Restructuring Cost And Reserve [Line Items]
Total	$ 2.4	$ 18.6	$ 46.8