EARNINGS (LOSS) PER SHARE - Schedule of Antidilutive Securities (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	11,328,000	12,712,000	15,710,000	12,712,000
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	55,000	2,485,000	199,000	2,485,000
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock equivalents excluded from calculation of diluted net (loss) income per share (in shares)	11,273,000	10,227,000	15,511,000	10,227,000