FAIR VALUE MEASUREMENT - The liability component was valued based on the Income Approach (Details) - 2021 Notes [Member] - Fair Value, Inputs, Level 3 [Member]	12 Months Ended
Dec. 31, 2019 $ / shares
Stock price (USD)	$ 3.28
Expected term	1 year 10 months 17 days
Risk free rate	1.57%
Volatility	90.74%
Yield	11.02%

- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ References

No definition available.

+ Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
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Period Type:	instant

- Details

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- Details

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