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Stock-Based Compensation - Stock incentive plan and other information (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Sep. 17, 2020 | Sep. 05, 2019 | Sep. 24, 2018 | Sep. 07, 2017 | Aug. 25, 2016 | May 15, 2015 | Oct. 22, 2013 | Nov. 02, 2010 | Mar. 20, 2007
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized stock-based compensation expense | $ 395,000 |  | $ 395,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Stock option |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number | 607,370 |  | 607,370 |  | 625,565 | 399,779 |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, grants in period, gross |  | 0 | 3,000 | 0 | 226,000 |  |  |  |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number |  |  |  |  |  |  | 400,000 |  |  |  |  |  |  |  |  |
General and Administrative Expenses | Employees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated share-based compensation expense | $ 46,000 | $ 34,000 | $ 124,000 | $ 101,000 |  |  |  |  |  |  |  |  |  |  |  |
Research and Development Expenses | Employees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated share-based compensation expense | 21,000 | 16,000 | 62,000 | 47,000 |  |  |  |  |  |  |  |  |  |  |  |
Consultant | General and Administrative Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated share-based compensation expense | 47,000 | 49,000 | 141,000 | 147,000 |  |  |  |  |  |  |  |  |  |  |  |
Consultant | Research and Development Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated share-based compensation expense | $ 7,000 | $ 3,000 | $ 21,000 | $ 10,000 |  |  |  |  |  |  |  |  |  |  |  |
Employees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, grants in period, gross |  |  | 3,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Employees | General and Administrative Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Allocated share-based compensation expense |  |  | $ 5,000 |  |  |  |  |  |  |  |  |  |  |  |  |
2007 Stock Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number | 515 |  | 515 |  |  |  |  |  |  |  |  |  |  |  |  | 7,143
Amended Stock Plan 2010 | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number |  |  |  |  |  |  | 7,000,000 |  |  |  |  |  |  |  |  |
Common stock, capital shares reserved for future issuance |  |  |  |  |  |  |  |  | 400,000 | 100,000 | 50,000 | 40,000 | 22,858 | 17,143 |  |
Amended Stock Plan 2010 | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, capital shares reserved for future issuance |  |  |  |  |  |  |  |  | 100,000 | 50,000 | 40,000 | 22,858 | 17,143 | 8,572 |  |
2010 Stock Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number | 368,002 |  | 368,002 |  |  |  |  |  |  |  |  |  |  |  | 8,572 |
2010 Stock Plan | Board of Directors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number | 238,853 |  | 238,853 |  |  |  |  |  |  |  |  |  |  |  |  |
2020 Stock Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-Based Compensation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, options, outstanding, number |  |  |  |  |  |  |  | 400,000 |  |  |  |  |  |  |  |

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