STOCKHOLDERS EQUITY (DEFICIT) - Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 19, 2021	Dec. 29, 2020	Dec. 16, 2020	Apr. 29, 2020	Sep. 07, 2018	Sep. 06, 2018	Mar. 06, 2018	Dec. 31, 2016
Class of Stock [Line Items]
Warrants, exercisable price (in dollars per share)					$ 11.50
Loss from change in fair value of warrants		$ 45,625	$ 0
Term Loan Agreement Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)											49,223	96,300
Warrants, exercisable price (in dollars per share)											$ 1.94	$ 1.05
Investor Entity Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)						342,827	548,523		215,227
Warrants, exercisable price (in dollars per share)						$ 0.29	$ 0.29		$ 0.22
Warrants issued under met performance conditions (in shares)				21,522
Expense recognized				$ 1
Cash payment for warrant exercises	$ 47
Loss from change in fair value of warrants		$ 163	$ 331
Potential Customer Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)										717,424
Warrants, exercisable price (in dollars per share)										$ 2.79
Loan and Security Agreement Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)								30,000
Warrants, exercisable price (in dollars per share)								$ 2.92