v3.21.2

Warrant derivative liability (Placement Agent Warrants) (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
Apr. 05, 2017 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Nov. 15, 2017
Class of Warrant or Right, Outstanding |  |  |  |  | 896,739
Fair Value Adjustment of Warrants |  | $ 4 | $ 33 | $ 394 |
Placement Agent Warrants [Member] |  |  |  |  |
Warrants issued During Period | 34,783 |  |  |  |
Percentage Of Shares Issue To Placement Agent | 8.00% |  |  |  |
Class of Warrant or Right, Exercise Price of Warrants or Rights |  |  |  |  | $ 1.00
Class of Warrant or Right, Outstanding |  | 95,653 | 95,653 |  | 95,653
Warrants Not Settleable in Cash, Fair Value Disclosure |  | $ 46 | $ 30 |  |

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- Details
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