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Note 8 - Stock Plans (Details Textual) - USD ($) |  | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Jan. 22, 2026 | Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025 | Sep. 30, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value |  | $ 0 | $ 90,000 | $ 466,000 | $ 268,000 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value |  | $ 0 | 0 | $ 25,000 | 25,000 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares) |  | 315,000 |  | 315,000 |  |
Employee Stock Purchase Plan [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense |  | $ 16,000 | 10,000 | $ 31,000 | 18,000 |
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount |  | 31,000 |  | $ 31,000 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) |  |  |  | 6 months |  |
Stock Plan, Participation Period (Month) |  |  |  |  |  | 27 months
Percentage Of Employee Compensation That Can Be Withheld to Purchase Common Stock |  |  |  |  |  | 10.00%
Stock Purchase Price, Percentage of Price |  |  |  |  |  | 85.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) |  |  |  | $ 2.79 |  |
Share-Based Payment Arrangement, Option [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount |  | 0 |  | $ 0 |  |
Share-Based Payment Arrangement, Expense |  | 0 | 6,000 | 6,000 | 12,000 |
Restricted Stock [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense |  | $ 140,000 | $ 150,000 | $ 234,000 | $ 334,000 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) |  | $ 17.55 |  | $ 14.02 |  |
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount |  | $ 1,416,000 |  | $ 1,416,000 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) |  |  |  | 3 years |  |
O 2026 Q1 Dividends [Member] |  |  |  |  |  |
Dividends Payable, Date Declared | Jan. 22, 2026 |  |  |  |  |
Stock Dividend Declared, Percentage | 5.00% |  |  |  |  |
Dividends Payable, Date to be Paid | Mar. 25, 2026 |  |  |  |  |
Dividends Payable, Date of Record | Feb. 27, 2026 |  |  |  |  |

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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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