v3.10.0.1
NET LOSS PER SHARE - Reconciliation of basic and diluted net loss per share (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended 9 Months Ended
Sep. 30, 2018
Jun. 30, 2018
Sep. 30, 2017
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Earnings Per Share [Abstract]                
Net loss $ (1,865) $ (1,865) $ (1,537) $ (1,537) $ (9,557) $ (4,087) $ (9,557) $ (4,087)
Accretion of cumulative dividends of redeemable preferred stock to redemption value 0 0 (1,484) (1,484) 0 (4,364) 0 (4,364)
Net loss attributable to common stockholders - basic $ (1,865)   $ (3,021)       $ (9,557) $ (8,451)
Net loss attributable to common stockholders - diluted   $ (1,865)   $ (3,021) $ (9,557) $ (8,451)    
Weighted average number of shares - basic and diluted 12,624,858   1,773,385       12,417,972 1,754,576
Net loss per share attributable to common stockholders - basic and diluted (in dollars per share) $ (0.15)   $ (1.70)       $ (0.77) $ (4.82)