STOCKHOLDERS' EQUITY (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2021 shares	Sep. 30, 2021 shares	Dec. 31, 2020 shares
Common Stock | 2017 Warrants
Class of Warrant or Right [Line Items]
Number of shares purchasable through warrants (in shares)	1,400,000	1,400,000	1,400,000
Common Stock | 2015 Warrants
Class of Warrant or Right [Line Items]
Number of shares purchasable through warrants (in shares)	900,000	900,000	900,000
HC Group Holdings I, LLC
Class of Warrant or Right [Line Items]
Percentage of common stock		0.211
Common Stock | Public Offering | HC Group Holdings I, LLC
Class of Warrant or Right [Line Items]
Additional shares issued (in shares)	29,900,000	76,400,000