v3.19.2
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
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Earnings Per Share [Abstract]        
Net loss attributable to common stockholders $ (2,618) $ (2,692) $ (5,638) $ (7,692)
Weighted average common shares - basic and diluted (in shares) 14,451,979 12,549,226 14,409,752 12,312,814
Net loss per share attributable to common stockholders - basic and diluted (in dollars per share) $ (0.18) $ (0.21) $ (0.39) $ (0.62)