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Stockholders Equity (Equity Incentive Plans and Employee Stock Purchase Plan) (Details) - shares | 1 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2018 | Jun. 30, 2024 | Dec. 31, 2016 | Dec. 31, 2019
Stockholders' Equity |  |  |  |  |  |  |
Shares authorized |  |  |  |  |  |  | 26,667
Additional shares authorized | 400,000 |  | 40,000 |  |  |  |
Shares available for grant | 466,667 |  |  |  |  |  |
Predetermined offering period, lower fair market value percentage |  |  |  |  | 85.00% |  |
Number of shares purchased under ESPP |  |  |  |  | 128,352 |  |
Shares available for future sale |  |  |  |  | 338,315 |  |
Employee Stock Option |  |  |  |  |  |  |
Stockholders' Equity |  |  |  |  |  |  |
Shares authorized |  |  |  |  |  | 133,333 |
Expiration period |  |  |  |  |  | 10 years |
Additional shares authorized |  | 200,000 | 200,000 | 200,000 |  |  |
Shares available for grant |  | 733,333 | 533,333 | 333,333 |  |  |
Shares available for future sale |  |  |  |  | 394,393 |  |

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