Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 13,195	$ 131	$ 23,048	$ 760
Other comprehensive (loss) income:
Foreign currency exchange translation adjustments	(5,304)	2,256	(3,834)	4,078
Minimum pension liability, net of tax	(593)	(544)	(932)	(1,284)
Other comprehensive (loss) income	(5,897)	1,712	(4,766)	2,794
Comprehensive income	$ 7,298	$ 1,843	$ 18,282	$ 3,554