PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 270,630	$ 245,141
Less: accumulated depreciation	87,909	79,387
Property, plant and equipment, net	182,721	165,754
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	7,199	4,208
Building [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	55,260	45,735
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	189,265	177,841
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 18,906	$ 17,357