PROPERTY, PLANT AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 157,304	$ 149,104
Accumulated depreciation	(113,809)	(100,349)
Property, plant and equipment, net	43,495	48,755
Depreciation expense	14,000	14,800	$ 16,000
Land [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	2,259	2,234
Buildings and Improvements [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	30,761	30,061
Machinery and Equipment [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	122,773	113,780
Construction in Progress [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 1,511	$ 3,029