PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 242,616	$ 229,505
Less: accumulated depreciation	75,936	70,990
Property, plant and equipment, net	166,680	158,515
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,282	3,247
Building [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	45,677	33,051
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	175,679	153,682
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 16,978	$ 39,525