NET LOSS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
NET LOSS PER SHARE
Net loss	$ (5,171)	$ (2,922)	$ (12,591)	$ (27,002)
Weighted average common shares outstanding:
Basic	22,926,764	22,786,745	22,901,558	22,765,548
Diluted	22,926,764	22,786,745	22,901,558	22,765,548
Basic loss per share of common stock	$ (0.23)	$ (0.13)	$ (0.55)	$ (1.19)
Diluted loss per share of common stock	$ (0.23)	$ (0.13)	$ (0.55)	$ (1.19)