PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 152,239		$ 152,239		$ 149,104
Accumulated depreciation	(108,575)		(108,575)		(100,349)
Property, plant and equipment, net	43,664		43,664		48,755
Depreciation expense	3,600	$ 3,700	10,600	$ 11,100
Land [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	2,256		2,256		2,234
Buildings and Improvements [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	30,867		30,867		30,061
Machinery and Equipment [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	117,523		117,523		113,780
Construction in Progress [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 1,593		$ 1,593		$ 3,029