FAIR VALUE MEASUREMENTS AND FAIR VALUE OF FINANCIAL INSTRUMENTS - Significant unobservable inputs related to level 3 assets and liabilities (Details)	Dec. 31, 2019
Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.107
Probability of the occurrence of certain events
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.200
Level 3 | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.107
Level 3 | Probability of the occurrence of certain events
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative liability, measurement input	0.200