PROPERTY PLANT AND EQUIPMENT (NARRATIVE) (DETAILS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Depreciation and amortization expense for property, plant and equipment	$ 57,000	$ 59,100	$ 54,000
Property, plant and equipment, net	163,297	151,037
Software Development [Member]
Property, plant and equipment, net	$ 8,500	$ 10,100