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Note 11 - Stock-based Compensation (Details Textual) - The 2018 Equity Incentive Plan [Member] - USD ($) | 3 Months Ended |
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Mar. 31, 2025 | Mar. 31, 2024 | May 17, 2018
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares) |  |  | 1,300,000
Share-Based Payment Arrangement, Expense | $ 512,000 | $ 395,000 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expected Contractual Term Forfeiture Rate | 3.10% |  |
Share-Based Payment Arrangement, Tranche One [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 1 year |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year) | 5 years 6 months |  |
Share-Based Payment Arrangement, Tranche Three [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 2 years |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year) | 5 years 9 months |  |
Share-Based Payment Arrangement, Tranche Four [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 5 years |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year) | 6 years 6 months |  |
Restricted Stock [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares) |  |  | 326,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) | 38,372 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 8 months 12 days |  |
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount | $ 2,800,000 |  |
Restricted Stock [Member] | Director [Member] | Minimum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 1 year |  |
Restricted Stock [Member] | Director [Member] | Maximum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 2 years |  |
Restricted Stock [Member] | Officers And Employees [Member] | Maximum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 5 years |  |
Share-Based Payment Arrangement, Option [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) | 190,432 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year) | 10 years |  |
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount | $ 1,700,000 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 7 months 6 days |  |
Share-Based Payment Arrangement, Option [Member] | Maximum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year) | 10 years |  |
Share-Based Payment Arrangement, Option [Member] | Director [Member] | Minimum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 1 year |  |
Share-Based Payment Arrangement, Option [Member] | Director [Member] | Maximum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 2 years |  |
Share-Based Payment Arrangement, Option [Member] | Officers And Employees [Member] | Share-Based Payment Arrangement, Tranche One [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage | 20.00% |  |
Share-Based Payment Arrangement, Option [Member] | Officers And Employees [Member] | Maximum [Member] |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) | 5 years |  |

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