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Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 10, 2020 | Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares outstanding under Equity plan | 531,238 | 31,136 |  | 33,503
Weighted Average exercise Price of Options Outstanding | $ 8.71 | $ 84.50 |  | $ 96.22
Stock options award, expiration | 10 years |  |  |
Employee Stock Option |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Unrecognized compensation expense related to unvested options | $ 1.6 |  |  |
Maturity period of weighted average period of compensation expenses | 4 years |  |  |
Minimum |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Stock options award, vesting period | 3 years |  |  |
Percentage holding for stock options exercise price | 10.00% |  |  |
Minimum | Incentive Stock Option |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Percentage of exercise price of stock option | 100.00% |  |  |
Minimum | Incentive Stock Option | Stockholders |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Percentage of exercise price of stock option | 110.00% |  |  |
Maximum |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Stock options award, vesting period | 4 years |  |  |
2020 Equity Incentive Plan |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares issuable under Equity plan |  |  | 1,167,425 |
Number of shares outstanding under Equity plan | 494,100 |  |  |
Weighted Average exercise Price of Options Outstanding | $ 4.27 |  |  |
Shares reserved for future | 636,347 |  |  |
Options granted | 500,350 |  |  |
2013 Plan |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares outstanding under Equity plan | 36,978 |  |  |
Weighted Average exercise Price of Options Outstanding | $ 61.84 |  |  |
Options granted |  | 0 |  |
2004 Plan |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares outstanding under Equity plan | 160 |  |  |
Weighted Average exercise Price of Options Outstanding | $ 1,437.48 |  |  |

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