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

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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
	Dec. 28, 2019	Dec. 29, 2018	Feb. 17, 2015
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 222,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 193 days
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	$ 60,000	$ 55,000
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	$ 126,000	$ 119,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 281 days
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 356,000
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	143,000