SHARE-BASED COMPENSATION - Stock Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number of Shares under Option (in thousands)
Outstanding at beginning of period (in shares)	15,703	10,147	6,236
Granted (in shares)	1,510	8,273	4,044
Exercised (in shares)	(2)	(34)	(12)
Canceled or forfeited (in shares)	(1,907)	(2,683)	(121)
Outstanding at end of period (in shares)	15,304	15,703	10,147	6,236
Exercisable at end of period (in shares)	10,427
Weighted-Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 1.93	$ 1.26	$ 1.52
Granted (in dollars per share)	0.72	3.32	0.87
Exercised (in dollars per share)	0.32	1.23	1.13
Cancelled or forfeited (in dollars per share)	1.90	3.70	1.04
Outstanding at end of period (in dollars per share)	1.82	$ 1.93	$ 1.26	$ 1.52
Exercisable at end of period (in dollars per share)	$ 1.72
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-average Remaining Contractual Life (in years), Outstanding	7 years 2 months 8 days	8 years 10 days	8 years 6 months	8 years 9 months 29 days
Weighted-average Remaining Contractual Life (in years), Exercisable	6 years 9 months 7 days
Aggregate Intrinsic Value, Outstanding	$ 3	$ 82	$ 3,160	$ 358