SHARE-BASED COMPENSATION - Summary of Status and Changes of Unvested Restricted Stock (Details) - $ / shares	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Number of Shares
Unvested, beginning balance (in shares)	3,041,000
Unvested, ending balance (in shares)	8,063,000
Weighted-Average Grant Date Fair Value
Unvested beginning balance (in dollars per share)	$ 0.80
Unvested ending balance (in dollars per share)	$ 0.72
RSU
Number of Shares
Granted (in shares)	4,161,000	0
Cancelled RSU (in shares)	(143,000)
Weighted-Average Grant Date Fair Value
Granted (in dollars per share)	$ 0.68
Cancelled RSU (in dollars per share)	$ 0.75
PSUs
Number of Shares
Granted (in shares)	1,004,000	0
Weighted-Average Grant Date Fair Value
Granted (in dollars per share)	$ 0.67