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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 28, 2024 | Sep. 30, 2023 | Oct. 01, 2022
Depreciation |  | $ 14,700,000 | $ 12,500,000 | $ 13,700,000
Interest Costs Capitalized |  | 0 | 0 | 0
Goodwill, Impairment Loss |  | 0 | 0 | 0
Asset Impairment Charges |  | $ 0 | $ 0 | $ 0
Computer Software, Intangible Asset [Member] |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  | 5 years |  |
Machinery and Equipment [Member] | Minimum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life |  | 3 years |  |
Machinery and Equipment [Member] | Maximum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life |  | 15 years |  |
Building [Member] | Minimum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life |  | 10 years |  |
Building [Member] | Maximum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life |  | 30 years |  |
Land Improvements [Member] | Minimum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life |  | 10 years |  |
Land Improvements [Member] | Maximum [Member] |  |  |  |
Property, Plant and Equipment, Useful Life |  | 20 years |  |
Forecast [Member] |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | $ 878,000 |  |  |
Defined Benefit Plan, Expected Future Benefit Payment | 944,000 |  |  |
Defined Benefit Plan, Increase in Expected Net Periodic Benefit Cost (Credit), Next Twelve Months | $ 4,000 |  |  |
Decrease in Assumed Discount Rate [Member] |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 0.25% |  |
Defined Benefit Plan, Increase of Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets |  | $ 297,000 |  |
Defined Benefit Plan, Increase in Accumulated Benefit Obligation |  | $ 242,000 |  |

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