STOCKHOLDERS' EQUITY - Schedule of Variables used in Black-Scholes Model (Details)	Mar. 31, 2021	Dec. 31, 2020	Jul. 18, 2019
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Expected life (years)	3 years 9 months 21 days	4 years 21 days	5 years
Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input	0.64%	0.27%
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input	130.68%	130.56%
Expected dividend
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants measurement input	0.00%	0.00%