FAIR VALUE MEASUREMENTS - Quantitative information regarding the significant unobservable inputs for derivative liabilities (Details) - Level 3	Dec. 31, 2020
Term in years | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.3
Term in years | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	1.3
Calibrated Risk Premium
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.1168
Option Adjusted Spread
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.0803
Risk Free Rate | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.0012
Risk Free Rate | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Embedded derivative liability, measurement input	0.0019