Note 6 - Stock-based Compensation - Stock Option Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Employee Stock Option [Member]
Compensation expense	$ 51	$ 78	$ 522	$ 585

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.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
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