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Note 8 - Stock-based Compensation (Details Textual) - USD ($) | 1 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares) |  | 290,000 |  | 383,000
The 2025 Employee Stock Purchase Plan [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Discount from Market Price, Offering Date | 5.00% |  |  |
Common Stock, Capital Shares Reserved for Future Issuance (in shares) | 200,000 | 200,000 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Minimum Employee Payroll Deduction | $ 5 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Maximum Employee Payroll Deduction | $ 200 |  |  |
The 2025 Employee Stock Purchase Plan [Member] | Maximum [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Purchase Price of Common Stock, Percent | 95.00% |  |  |
Restricted Stock [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) |  | 3 years |  |
Performance Shares [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  | 24,910 |  |
Noninterest Expense [Member] |  |  |  |
Share-Based Payment Arrangement, Expense |  | $ 2,700,000 | $ 2,500,000 |

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- Definition Minimum employee payroll deduction that an employee is permitted to utilize with respect to the plan. + References No definition available. + Details
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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