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Note 12 - Income Taxes (Details Textual) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Dec. 31, 2024 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Sep. 30, 2024
Effective Income Tax Rate Reconciliation, at Federal and State Statutory Income Tax Rate, Percent | 25.74% |  | 25.74% | 25.74% | 25.74% |
Unrecognized Tax Benefits | $ 273,936 |  |  | $ 273,936 |  | $ 273,936
Income Tax Examination, Year under Examination |  |  |  | 2018 2019 |  |
Domestic Tax Jurisdiction [Member] | Internal Revenue Service (IRS) [Member] |  |  |  |  |  |
Open Tax Year |  |  |  | 2018 2019 |  |
State and Local Jurisdiction [Member] | Virginia, Jurisdiction [Member] |  |  |  |  |  |
Open Tax Year |  | 2022 2023 2024 2025 |  |  |  |

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