PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Property, plant and equipment
Property, plant and equipment, gross	$ 185,761	$ 183,786
Accumulated depreciation	(122,010)	(117,912)
Property, plant and equipment, net	63,751	65,874
Land, buildings and improvements
Property, plant and equipment
Property, plant and equipment, gross	83,531	83,119
Machinery, equipment and fixtures
Property, plant and equipment
Property, plant and equipment, gross	79,382	78,003
Office furniture, equipment and vehicles
Property, plant and equipment
Property, plant and equipment, gross	22,626	22,265
Construction in progress
Property, plant and equipment
Property, plant and equipment, gross	$ 222	$ 399