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Stock-Based Compensation and Warrants (Details 4) - $ / 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 14 days | 1 year 9 months 14 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
Series B Warrants [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Closing stock price |  | $ 31.15 |  |
Expected dividends |  | 0.00% |  |
Expected volatility |  | 85.00% |  |
Risk free interest rate |  | 0.81% |  |
Expected life of warrant |  | 1 year 1 month 6 days |  |

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