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WARRANT LIABILITY AND FAIR VALUE MEASUREMENTS (Tables) | 9 Months Ended
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Sep. 30, 2020
WARRANT LIABILITY AND FAIR VALUE MEASUREMENTS |
Schedule of valuation methodology | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Weighted Average Inputs | ​
​ | ​ | For the Nine Months Ended | ​
​ | ​ | September 30, | ​
​ |  | 2020 |  | 2019 | ​
Exercise price | ​ | $ | — | ​ | $ | 6.92 | ​
Contractual term (years) | ​ |  | — | ​ |  | 0.30 | ​
Volatility (annual) | ​ |  | — | ​ |  | 92 | %
Risk-free rate | ​ |  | — | ​ |  | 2 | %
Dividend yield (per share) | ​ |  | — | ​ |  | 0 | %
Schedule of financial liabilities measured at fair value on a recurring basis | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Fair value measured at September 30, 2020
​ | ​ | Quoted prices in active | ​ | Significant other | ​ | Significant | ​ | ​ | ​
​ | ​ | markets | ​ | observable inputs | ​ | unobservable inputs | ​ | Fair value at
​ |  | (Level 1) |  | (Level 2) |  | (Level 3) |  | September 30, 2020
Warrant liability | ​ | $ | — | ​ | $ | — | ​ | $ | — | ​ | $ | —
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Fair value measured at December 31, 2019
​ | ​ | Quoted prices in active | ​ | Significant other | ​ | Significant | ​ | ​ | ​
​ | ​ | markets | ​ | observable inputs | ​ | unobservable inputs | ​ | Fair value at
​ |  | (Level 1) |  | (Level 2) |  | (Level 3) |  | December 31, 2019
Warrant liability | ​ | $ | — | ​ | $ | — | ​ | $ | 31,000 | ​ | $ | 31,000
Schedule of Changes in Level 3 Liabilities Measured at Fair Value | ​
​ | ​ | ​ | ​
​ |  | Warrant
​ | ​ | Liability
Balance - January 1, 2020 | ​ | $ | 31,000
Change in fair value of warrant liability | ​ |  | (31,000)
Balance – September 30, 2020 | ​ | $ | —

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