Restructuring - Summary of Activity of Restructuring (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			$ 22,335
Restructuring	$ 2,703	$ 9,909	19,841	$ 28,220
Cash payments			(31,176)
Foreign exchange translation and other			(623)
Restructuring Reserve, Ending Balance	10,377		10,377
Employee Separation Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			15,091
Restructuring			13,118
Cash payments			(20,591)
Foreign exchange translation and other			(521)
Restructuring Reserve, Ending Balance	7,097		7,097
Other Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Beginning Balance			7,244
Restructuring			6,723
Cash payments			(10,585)
Foreign exchange translation and other			(102)
Restructuring Reserve, Ending Balance	$ 3,280		$ 3,280