Business Restructuring - Reconciliation of Restructuring Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Restructuring Cost And Reserve [Line Items]
Restructuring liability	$ 691
Expense recognized	358	$ 786
Amounts paid	(549)
Foreign currency translation	(7)
Restructuring liability	493
Termination Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring liability	592
Amounts paid	(140)
Foreign currency translation	(3)
Restructuring liability	449
Other Expense [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring liability	99
Expense recognized	358
Amounts paid	(409)
Foreign currency translation	(4)
Restructuring liability	$ 44