NET LOSS PER COMMON SHARE - EPS (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Numerator:    
Net loss attributable to common stockholders-basic $ (105,584) $ (93,961)
Net loss attributable to common stockholders-diluted $ (105,584) $ (93,961)
Denominator:    
Weighted-average common stock outstanding-basic 25,598,181 21,966,326
Weighted-average common stock outstanding-diluted 25,598,181 21,966,326
Net loss per share attributable to common stockholders-basic $ (4.12) $ (4.28)
Net loss per share attributable to common stockholders-diluted $ (4.12) $ (4.28)