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Note 3 - Recent Accounting Pronouncements (Details Textual) - USD ($) $ in Millions | 12 Months Ended
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Sep. 29, 2018 | Sep. 30, 2017 | Oct. 01, 2016
Accounting Standards Update 2016-09 [Member] |  |  |
Excess Tax Benefit from Share-based Compensation, Operating Activities |  | $ 0.5 | $ 1.7
Excess Tax Benefit from Share-based Compensation, Financing Activities |  | $ (0.5) | $ (1.7)
Retained Earnings [Member] |  |  |
Tax Cuts and Jobs Act, Reclassification of Stranded Tax Effects from AOCI to Retained Earnings, Tax Effect | $ 0.3 |  |
AOCI Attributable to Parent [Member] |  |  |
Tax Cuts and Jobs Act, Reclassification of Stranded Tax Effects from AOCI to Retained Earnings, Tax Effect | $ (0.3) |  |

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- Definition Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109196918&loc=d3e11374-113907 + Details
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