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

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Note 7 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		6 Months Ended
	Feb. 28, 2020	Apr. 02, 2022	Apr. 03, 2021	Apr. 02, 2022	Apr. 03, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 15.45	$ 12.33
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)				10 years
Share-based Payment Arrangement, Expense		$ 374,000	$ 324,000	$ 480,000	$ 400,000
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		624,000		$ 624,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				2 years 2 months 12 days
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense		$ 455,000	$ 386,000	$ 622,000	$ 534,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 8 months 1 day
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		$ 1,100,000		$ 1,100,000
Restricted Stock Units (RSUs) [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				1 year
Restricted Stock Units (RSUs) [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				3 years
The 2015 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	750,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)		620,000		620,000