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Stock-Based Payments - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 01, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Jul. 02, 2021 | May 25, 2021 | May 15, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Number of stock option issued |  |  |  |  | 554,615 |  |  |  |
Share-based compensation expense |  | $ 740 |  | $ 450 | $ 3,896 | $ 2,021 |  |  |
Chief Executive Officer |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Reduction in stock-based compensation expense |  | 100 |  |  | 100 |  |  |  |
Chief Operating Officer |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Share-based compensation expense |  | 500 |  |  | $ 500 |  |  |  |
Employee and Director Stock Options |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Number of stock option issued |  |  |  |  | 554,615 |  |  |  |
Stock option forfeited |  |  |  |  | 13,200 |  |  |  |
Unrecognized compensation cost related to non-vested stock options outstanding |  | 3,000 |  |  | $ 3,000 |  |  |  |
Weighted-average remaining vesting period |  |  |  |  | 3 years 4 months 24 days |  |  |  |
Unrecognized compensation cost related to Performance-based stock options |  | 1,200 |  |  | $ 1,200 |  |  |  |
Weighted average grant date fair value |  |  |  |  | $ 10.67 |  |  |  |
Consultants Stock Options |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Number of stock option issued |  |  |  |  | 0 |  |  |  |
Unrecognized compensation cost related to non-vested stock options outstanding |  | $ 3 |  |  | $ 3 |  |  |  |
Weighted-average remaining vesting period |  |  |  |  | 1 month 6 days |  |  |  |
Restricted Stock Units |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares granted |  |  |  |  | 9,871 |  |  |  |
Restricted Stock Units | Board of Directors |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares granted |  |  |  |  | 6,343 |  |  |  |
Vesting period in installments |  |  |  |  | 12 months |  |  |  |
2018 Omnibus Incentive Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock shares authorized and approved to issue under plan |  |  |  |  |  |  |  | 565,000 | 153,031
Common stock shares available for issuance |  |  |  |  |  |  |  |  | 85,714
Common stock remaining available for grant |  | 139,139 |  |  | 139,139 |  |  |  |
2018 Omnibus Incentive Plan | Restricted Stock Units | Officer |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares granted |  |  | 2,668 |  |  |  |  |  |
Scheduled to vest date |  |  | Oct. 02, 2021 |  |  |  |  |  |
2018 Omnibus Incentive Plan | Unrestricted Stock | Officer | Class A Common Stock |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Shares granted | 5,337 |  |  |  |  |  |  |  |
2016 Omnibus Incentive Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock shares available for issuance |  |  |  |  |  |  |  |  | 67,317
2021 Inducement Plan |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock remaining available for grant |  | 80,000 |  |  | 80,000 |  |  |  |
2021 Inducement Plan | Common Stock |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Common stock shares available for issuance |  |  |  |  |  |  | 100,000 |  |

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