Consolidated Statements of Operations and Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net Sales	$ 125,284	$ 120,339	$ 251,359	$ 240,205
Costs and expenses:
Cost of products sold	76,310	71,344	155,152	143,584
Selling	15,249	15,936	30,926	31,610
General and administrative	17,216	15,263	30,313	27,686
Research and development	1,613	1,666	3,181	3,410
Restructuring	206	874	1,030	4,038
Costs and expenses	110,594	105,083	220,602	210,328
Income from operations	14,690	15,256	30,757	29,877
Interest expense, net	(13,130)	(13,281)	(25,895)	(26,544)
Other components of net periodic pension cost	(262)	(307)	(528)	(668)
Loss on extinguishment of debt	0	(7)	0	(32)
Foreign exchange loss	(3,126)	(1,246)	(2,594)	(2,371)
(Loss) income before provision for income taxes	(1,828)	415	1,740	262
Provision for income taxes	(2,516)	(3,826)	(3,853)	(6,507)
Net loss	(4,344)	(3,411)	(2,113)	(6,245)
Comprehensive (loss) income	$ (23,139)	$ (146)	$ (14,777)	$ 6,660
Net loss per share:
Basic (in dollars per share)	$ (0.26)	$ (0.21)	$ (0.13)	$ (0.39)
Diluted (in dollars per share)	$ (0.26)	$ (0.21)	$ (0.13)	$ (0.39)
Shares used in computing net loss per share:
Basic (in shares)	16,427,603	16,262,867	16,412,921	16,208,293
Diluted (in shares)	16,427,603	16,262,867	16,412,921	16,208,293