v3.8.0.1
NET LOSS PER SHARE - Calculation of Basic and Diluted Net Income Per Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Numerator:        
Net loss $ (6,612) $ (9,712) $ (19,504) $ (29,647)
Denominator:        
Weighted-average shares used to compute net loss per share, basic and diluted 53,683,727 50,818,710 53,070,863 49,920,630
Basic (in dollars per share) $ (0.12) $ (0.19) $ (0.37) $ (0.59)