Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Loss [Abstract]
Pension and post-retirement benefit plan adjustments	$ (4,439)	$ (3,069)
Unrealized loss on interest rate swap contracts	(204)	(121)
Foreign currency translation adjustments	(20,646)	(14,750)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Total	$ (25,289)	$ (17,940)