FAIR VALUE OF MEASUREMENTS AND INVESTMENT SECURITIES - Fair Value of Warrants (Details) - Warrant Derivative Liability		9 Months Ended	12 Months Ended
Aug. 21, 2019	Sep. 30, 2019	Dec. 31, 2019
Derivative [Line Items]
Risk-free interest rate	1.54%	1.62%	1.83%
Volatility	69.72%	70.89%	78.67%
Expected life	7 years	6 years 10 months 21 days	6 years 7 months 21 days

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification
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