STOCK AWARD PLAN AND STOCK-BASED COMPENSATION - Summary of Assumptions Used in Black Scholes Model to Estimate Fair Value of Stock Options (Details) - $ / shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Stock Award Plan and Stock-Based Compensation
Dividend yield	0.00%
Weighted average grant date fair value per share of common stock	$ 5.17
Employee Stock Option
Stock Award Plan and Stock-Based Compensation
Expected term (years)		6 years 3 months
Risk free interest rate		2.33%
Volatility		83.00%
Dividend yield		0.00%
Weighted average grant date fair value per share of common stock		$ 4.47
Non-Employees Stock Options
Stock Award Plan and Stock-Based Compensation
Dividend yield		0.00%
Weighted average reporting date fair value per share of common stock		$ 5.56
Non-Employees Stock Options \| Minimum
Stock Award Plan and Stock-Based Compensation
Expected term (years)		8 years 4 months 24 days
Risk free interest rate		2.71%
Volatility		85.00%
Non-Employees Stock Options \| Maximum
Stock Award Plan and Stock-Based Compensation
Expected term (years)		9 years 9 months 18 days
Risk free interest rate		2.74%
Volatility		113.00%

Share based compensation arrangement by share based payment award options grants in period weighted average fair value.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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

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.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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