Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Note 6 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018	Feb. 17, 2015
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 214,000		$ 214,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year 200 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 7.96	$ 10.46
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	58,000	$ 51,000	$ 496,000	$ 522,000
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	124,000	$ 117,000	$ 705,000	719,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition			1 year 171 days
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture, Total			$ 763,000	$ 712,000
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 486,000		$ 486,000
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	241,000		241,000