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Stock-Based Compensation and Warrants - Assumptions (Details) - $ / shares |  | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Oct. 10, 2014 | Oct. 10, 2014 | Nov. 18, 2016 | Dec. 31, 2018 | Oct. 10, 2018 | Dec. 26, 2017
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |  |
Closing stock price | $ 61.25 | $ 61.25 |  | $ 0.56 | $ 0.88 | $ 18.55
Expected volatility | 95.00% |  |  | 110.00% |  |
Risk free interest rate | 1.39% |  |  | 2.60% |  |
Expected life of warrant (years) | 5 years | 5 years |  | 9 months 15 days |  |
Series A Warrants [Member] |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |  |  |
Closing stock price |  |  | $ 31.15 | $ 0.56 |  |
Expected volatility |  |  | 85.00% | 92.50% |  |
Risk free interest rate |  |  | 1.58% | 2.50% |  |
Expected life of warrant (years) |  |  | 4 years | 1 year 10 months 24 days |  |

X
- 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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