GEOGRAPHIC AND SEGMENT INFORMATION - REPORTABLE SEGMENT (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Sales	$ 3,672	$ 2,651	$ 10,760	$ 6,576
(Loss) income from operations	(2,788)	(2,833)	(8,441)	(10,648)
Interest income (expense), net	105	(36)	33	(103)
Other losses	(868)	0	(868)	0
Change in fair value of derivative liabilities	0	(69)	20	57
Income tax (benefit) expense	(2,408)	6	(2,384)	15
Depreciation and amortization	58	171	429	527
Operating Segments | Advanced Energy
Segment Reporting Information [Line Items]
Sales	2,985	2,126	8,727	4,546
(Loss) income from operations	(1,155)	(718)	(2,525)	(3,821)
Interest income (expense), net	0	0	0	0
Other losses	0		0
Change in fair value of derivative liabilities		0	0	0
Income tax (benefit) expense	0	0	0	0
Depreciation and amortization	0	0	0	0
Operating Segments | OEM
Segment Reporting Information [Line Items]
Sales	687	525	2,033	2,030
(Loss) income from operations	368	323	1,076	1,031
Interest income (expense), net	0	0	0	0
Other losses	0		0
Change in fair value of derivative liabilities		0	0	0
Income tax (benefit) expense	0	0	0	0
Depreciation and amortization	0	0	0	0
Corporate (Other)
Segment Reporting Information [Line Items]
Sales	0	0	0	0
(Loss) income from operations	(2,001)	(2,438)	(6,992)	(7,858)
Interest income (expense), net	105	(36)	33	(103)
Other losses	(868)		(868)
Change in fair value of derivative liabilities		(69)	20	57
Income tax (benefit) expense	(2,408)	6	(2,384)	15
Depreciation and amortization	$ 58	$ 171	$ 429	$ 527