v3.20.4

Stockholders' Equity - Equity Incentive Plans - Additional Information (Details) | 12 Months Ended
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Dec. 31, 2020 Plan
Class Of Stock [Line Items] |
Number of equity incentive plans | 2
2008 Plan and 2017 Plan | Employee Stock Option |
Class Of Stock [Line Items] |
Percentage of voting rights | 10.00%
2008 Plan and 2017 Plan | Employee Stock Option | Minimum | 10% Shareholder |
Class Of Stock [Line Items] |
Stock option fair market value at the date of grant, percent | 110.00%

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