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Fair Value Measurements (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Warrant liability | $ 170 | $ (210) |
Warrant [Member] | Securities Purchase Agreement [Member] |  |  |
Term expiration date | Jun. 21, 2022 | Jun. 21, 2022 |
Exercise price | $ 2.05 | $ 2.05 |
Volatility rate | 90.00% | 90.00% |
Risk-free interest rate | 2.15% | 2.01% |
Stock price | $ 1.50 |  |
Warrant liability | $ 1,200 |  |
Warrant exercise price | $ 1.20 |  |

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