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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Note 6 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended
	Feb. 28, 2020	Dec. 31, 2022	Jan. 01, 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		$ 36,000	$ 105,000
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 463,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		1 year 10 months 13 days
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Expense		$ 94,000	$ 167,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		1 year 7 months 2 days
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		$ 710,000
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		582,000