PROPERTY PLANT AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	$ 270,588		$ 270,588		$ 266,184
Less: accumulated depreciation	(179,210)		(179,210)		(172,569)
Total property, plant, and equipment, net	91,378		91,378		93,615
Depreciation expense	7,500	$ 7,400	14,800	$ 15,100
Land
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	644		644		644
Buildings
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	26,535		26,535		28,180
Furniture and fixtures
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	13,876		13,876		12,968
Machinery and equipment
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	27,405		27,405		26,838
Therapeutic program equipment leased to third parties under operating leases
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	29,355		29,355		31,100
Leasehold improvements
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	105,396		105,396		100,999
Computers and software
Property, Plant and Equipment, Net
Total property, plant, and equipment, gross	$ 67,377		$ 67,377		$ 65,455