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v3.19.2

Stock Warrants - Warrant liability (Details) - $ / shares |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 10, 2014 | Nov. 18, 2016 | Dec. 31, 2018 | Dec. 31, 2017
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Closing stock price | $ 61.25 |  | $ 0.56 | $ 17.85
Expected dividends | 0.00% |  | 0.00% | 0.00%
Expected volatility | 95.00% |  | 110.00% | 80.00%
Risk free interest rate | 1.39% |  | 2.60% | 1.86%
Expected life of warrant | 5 years |  | 9 months 15 days | 1 year 9 months 15 days
Series A Warrants [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Closing stock price |  | $ 31.15 | $ 0.56 | $ 17.85
Expected dividends |  | 0.00% | 0.00% | 0.00%
Expected volatility |  | 85.00% | 92.50% | 80.00%
Risk free interest rate |  | 1.58% | 2.50% | 1.97%
Expected life of warrant |  | 4 years | 1 year 10 months 24 days | 2 years 10 months 24 days

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- 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 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 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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- 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. + References No definition available. + Details
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- Details
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