ORGANIZATION, BASIS OF PRESENTATION, AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Earnings (Loss) Per Share, Potentially Dilutive Securities (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total common stock equivalents (in shares)	27,965,337	22,089,697
Redeemable convertible series 1 preferred stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total common stock equivalents (in shares)	4,520,000	5,340,000
Warrants to purchase common stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total common stock equivalents (in shares)	11,616,080	5,750,000
Private placement option
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total common stock equivalents (in shares)	9,675,000	9,675,000
Options to purchase common stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total common stock equivalents (in shares)	1,985,277	1,142,470
Unvested shares of restricted stock units
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Total common stock equivalents (in shares)	168,980	182,227