PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 245,141	$ 229,505
Less: Accumulated depreciation	79,387	70,990
Property, plant and equipment, net	165,754	158,515
Depreciation expense	15,907	12,895	$ 10,599
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,208	3,247
Building [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	45,735	33,051
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	177,841	153,682
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 17,357	$ 39,525