Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 43,209	$ 41,151	$ 36,094
Other comprehensive (loss) income:
Foreign currency translation adjustment	(20,112)	(16,331)	479
Net gain (loss) on pension and other postretirement benefits	544	(4,938)	6,706
Other comprehensive (loss) income before income tax (benefit) expense	(19,568)	(21,269)	7,185
Income tax (expense) benefit related to items of other comprehensive (loss) income	(152)	1,872	(2,516)
Other comprehensive (loss) income	(19,720)	(19,397)	4,669
Comprehensive income	$ 23,489	$ 21,754	$ 40,763