PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 52,107		$ 52,107		$ 54,060
Less accumulated depreciation	(36,789)		(36,789)		(38,079)
Total property and equipment, net	15,318		15,318		15,981
Depreciation and amortization	900	$ 1,000	1,900	$ 2,100
Operating leases, gross	10,300		10,300		10,800
Operating leases, accumulated depreciation	5,700		5,700		6,100
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	377		377		377
Building
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,978		2,978		2,978
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	31,013		31,013		33,087
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,700		1,700		1,687
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,749		4,749		4,704
Leasehold and building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	9,981		9,981		9,953
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,309		$ 1,309		$ 1,274
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life			5 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Property plant and equipment, useful life			7 years