PROPERTY AND EQUIPMENT - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 15,540	$ 23,837
Less: Accumulated depreciation and amortization	(11,667)	(10,773)
Property and equipment, net	3,873	13,064
Furniture and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,600	2,237
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,731	11,391
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	351	351
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 9,858	$ 9,858

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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