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Note 10 - Stock-based Compensation Stock (Details Textual) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Oct. 31, 2025 shares | Jun. 30, 2025 shares | Dec. 31, 2025 USD ($) shares | Dec. 31, 2024 USD ($) shares | Jan. 01, 2025 shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross |  |  | 466,600 |  |
Executive Officer [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross |  |  | 0 | 39,721 |
Share-Based Payment Arrangement, Option [Member] |  |  |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $ |  |  | $ 1,900,000 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  |  | 2 years |  |
Stock Option Vesting Terms As Improbable to Probable [Member] | Chief Financial Officer [Member] |  |  |  |  |
Share-Based Payment Arrangement, Plan Modification, Incremental Cost | $ |  |  |  | $ 300,000 |
Share-Based Payment Arrangement, Accelerated Cost | $ |  |  | $ 12,000 |  |
Stock Option Vesting Terms As Improbable to Probable [Member] | Chief Operating Officer [Member] |  |  |  |  |
Share-Based Payment Arrangement, Plan Modification, Incremental Cost | $ |  |  | 200,000 |  |
Share-Based Payment Arrangement, Accelerated Cost | $ |  |  | $ 100,000 |  |
Equity Incentive Plan 2015 [Member] |  |  |  |  |
Percentage of Total Shares Eligible for Plan Reserve, On an Annual Basis |  |  | 4.00% |  |
Share Based Compensation Arrangement By Share Based Payment Award, Number of Shares Available for Grant, Increase (in shares) |  |  |  |  | 348,109
The 2018 Employee, Director and Consultant Equity Incentive Plan [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) |  |  | 0 |  |
The 2018 Employee, Director and Consultant Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period |  |  | 10 years |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period |  |  | 4 years |  |
The 2018 Employee, Director and Consultant Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Share-Based Payment Arrangement, Tranche One [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period |  |  | 1 year |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage |  |  | 25.00% |  |
Inducement Options [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period | 10 years | 10 years |  | 10 years |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period | 36 months | 36 months |  | 36 months |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross | 75,000 | 54,000 |  | 71,712 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Employees |  |  |  | 5 |
The 2025 Equity Plan [Member] |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) |  |  | 735,200 |  |

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