STOCK-BASED COMPENSATION - Schedule of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares
Options
Outstanding, beginning balance (in shares) | shares	4,903,839
Granted (in shares) | shares	1,882,450
Exercised (in shares) | shares	(4,973)
Canceled or forfeited (in shares) | shares	(1,042,595)
Outstanding, ending balance (in shares) | shares	5,738,721	4,903,839
Options vested or expected to vest (in shares) | shares	5,738,721
Options exercisable (in shares) | shares	2,650,851
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 17.38
Granted (in dollars per share) | $ / shares	3.33
Exercised (in dollars per share) | $ / shares	3.20
Cancelled or forfeited (in dollars per share) | $ / shares	16.16
Outstanding, ending balance (in dollars per share) | $ / shares	13.00	$ 17.38
Options vested or expected to vest (in dollars per share) | $ / shares	13.00
Options exercisable (in dollars per share) | $ / shares	$ 15.78
Weighted Average Remaining Life and Intrinsic Value
Options outstanding, remaining life (in years)	7 years 9 months 18 days	7 years 7 months 6 days
Options vested or expected to vest, remaining life (in years)	7 years 9 months 18 days
Options exercisable, remaining life (in years)	6 years 7 months 6 days
Options outstanding, intrinsic value | $	$ 27	$ 847
Options vested or expected to vest, intrinsic value | $	27
Options exercisable, intrinsic value | $	$ 27