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Stock Based Compensation - Additional Information (Details) - USD ($) $ in Thousands |  |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2021 | Jan. 01, 2018 | Nov. 09, 2017 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Common stock reserved for future issuance (in shares) |  |  |  | 3,601,238 |  | 3,601,238 |  | 2,725,956
Estimated grant date fair value of options vested |  |  |  | $ 153 | $ 193 | $ 199 | $ 322 |
Unrecognized cost for stock based compensation |  |  |  | $ 5 |  | $ 5 |  |
Stock options issued and outstanding |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Number of options, granted (in shares) |  |  |  | 0 | 0 | 0 | 0 |
Unrecognized cost for stock based compensation, period for recognition (in years) |  |  |  |  |  | 1 month 2 days |  |
Restricted stock units issued and outstanding |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Common stock reserved for future issuance (in shares) |  |  |  | 369,614 |  | 369,614 |  | 450,614
Unrecognized cost for stock based compensation, period for recognition (in years) |  |  |  |  |  | 2 years 10 months 9 days |  |
Unrecognized compensation cost related to non-vested RSUs |  |  |  | $ 25,509 |  | $ 25,509 |  |
2010 Plan |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Shares available for grant (in shares) |  |  |  | 0 |  | 0 |  |
2017 Plan |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Common stock reserved for future issuance (in shares) |  |  | 1,050,000 |  |  |  |  |
Common stock reserved for future issuance, percent increase |  | 5.00% |  |  |  |  |  |
Increase in shares available for grant (in shares) | 1,120,650 |  |  |  |  |  |  |
2017 Plan | Stock options issued and outstanding |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting period (in years) |  |  | 4 years |  |  |  |  |
Contractual life (in years) |  |  | 10 years |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Service period |  |  | 4 years |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Non-employee Board of Directors |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 25.00% |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting period (in years) |  |  | 4 years |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives | Year one vesting |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 50.00% |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives | First quarter vesting |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 12.50% |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives | Second quarter vesting |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 12.50% |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives | Third quarter vesting |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 12.50% |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives | First quarter vesting |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 12.50% |  |  |  |  |
2017 Plan | Restricted stock units issued and outstanding | Executives | Year two, three and four vesting |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting percentage |  |  | 50.00% |  |  |  |  |

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