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Note 8 - Stock-based Compensation (Details Textual) - USD ($) | 12 Months Ended |
--- | --- | ---
Sep. 29, 2018 | Sep. 30, 2017 | Oct. 01, 2016 | Feb. 17, 2015
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options | $ 262,000 |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | 1 year 240 days |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ 12.06 | $ 11.08 | $ 9.92 |
Employee Stock 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 |  |  |
Allocated Share-based Compensation Expense, Total | $ 906,000 | $ 1,000,000 | $ 988,000 |
Restricted Stock Units (RSUs) [Member] |  |  |  |
Allocated Share-based Compensation Expense, Total | $ 1,172,000 | $ 1,238,000 | $ 1,451,000 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | 1 year 270 days |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options | $ 451,000 |  |  |
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 Shares Authorized |  |  |  | 900,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 334,000 |  |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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