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Note 9 - Stock-based Compensation (Details Textual) - USD ($) |  | 12 Months Ended
--- | --- | ---
Feb. 11, 2020 | Sep. 28, 2024 | Sep. 30, 2023 | Oct. 01, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value |  | $ 13.01 | $ 13.27 | $ 14.67
Share-Based Payment Arrangement, Option [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period |  | 3 years |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period |  | 10 years |  |
Share-Based Payment Arrangement, Expense |  | $ 1,400,000 | $ 1,000,000 | $ 1,100,000
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount |  | $ 692,000 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  | 2 years 2 months 26 days |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |
Share-Based Payment Arrangement, Expense |  | $ 1,730,000 | $ 1,392,000 | $ 1,365,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  | 1 year 9 months |  |
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount |  | $ 1,100,000 |  |
Restricted Stock Units (RSUs) [Member] | Director [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period |  | 1 year |  |
Restricted Stock Units (RSUs) [Member] | Employees [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period |  | 3 years |  |
The 2015 Equity Incentive Plan [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized | 750,000 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant |  | 285,000 |  |

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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 S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1 Reference 2: 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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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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