Restructuring and Other - Multi-Employer Pension Plan Charges - Narrative (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Restructuring Cost And Reserve [Line Items]
Multi-employer pension plan charges	$ 0.6	$ 0.6
Accrued liabilities	349.2		$ 447.5
Other noncurrent liabilities	208.6		$ 180.2
Multi-employer pension plan withdrawal obligations
Restructuring Cost And Reserve [Line Items]
Accrued liabilities	5.1
Other noncurrent liabilities	$ 31.0