Restructuring, Impairment and Other Charges - Schedule of Changes in the Restructuring Reserve (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost And Reserve [Line Items]
Balance at the beginning			$ 21.0
Restructuring Charges	$ 3.5	$ 6.9	11.5	$ 13.3
Foreign Exchange and Other			0.6
Cash Paid			(9.9)
Balance at the end	23.2		23.2
Employee terminations
Restructuring Cost And Reserve [Line Items]
Balance at the beginning			7.6
Restructuring Charges			8.8
Foreign Exchange and Other			(0.3)
Cash Paid			(7.6)
Balance at the end	8.5		8.5
Lease terminations and other
Restructuring Cost And Reserve [Line Items]
Balance at the beginning			1.6
Restructuring Charges			2.4
Foreign Exchange and Other			0.9
Cash Paid			(1.6)
Balance at the end	3.3		3.3
Multi-employer pension plan withdrawal obligations
Restructuring Cost And Reserve [Line Items]
Balance at the beginning			11.8
Restructuring Charges			0.3
Cash Paid			(0.7)
Balance at the end	$ 11.4		$ 11.4