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Note 6 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		9 Months Ended
	Feb. 28, 2020	Jul. 01, 2023	Jul. 02, 2022	Jul. 01, 2023	Jul. 02, 2022
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		$ 160,000	$ 115,000	$ 635,000	$ 594,000
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		503,000		$ 503,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 11 months 8 days
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Expense		261,000	$ 178,000	$ 899,000	$ 801,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 5 months 12 days
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		$ 980,000		$ 980,000
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 Additional Shares Authorized	750,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		500,000		500,000