PROPERTY PLANT AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Jan. 01, 2019	Dec. 31, 2018
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	$ 268,715			$ 276,288
Less: accumulated depreciation and amortization	(186,764)			(186,799)
Total property, plant, and equipment, net	81,951		$ 81,421	89,489
Depreciation expense	7,500	$ 7,400
Land
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	634			644
Buildings
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	3,979			24,558
Furniture and fixtures
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	13,273			13,121
Machinery and equipment
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	26,568			27,452
Equipment leased to third parties under operating leases
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	29,402			30,093
Leasehold improvements
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	125,280			111,247
Computers and software
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	$ 69,579			$ 69,173