SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Thousands			2 Months Ended	12 Months Ended
	Mar. 12, 2018	Jan. 25, 2018	Mar. 12, 2018	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Subsequent events
Common stock, par value (in dollars per share)					$ 0.00001	$ 0.00001
Common Stock
Subsequent events
Issuance of stock in public offering (in shares)				2,388,245
Subsequent event | Common Stock | Purchase and registration rights agreement
Subsequent events
Aggregate proceeds		$ 15,000
Term		24 months
Common stock, par value (in dollars per share)		$ 0.00001
Drawn	$ 2,252
Issuance of stock in public offering (in shares)		429,800	3,344,769