Note 6 - Stock-based Compensation - RSU Grants and Compensation Expense (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Units (in shares)			24	19
Market value			$ 712	$ 690
Compensation expense	$ 117	$ 132	$ 719	$ 758

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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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Value, after forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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