Note 11 - Stock Ownership Plans - Stock Option Activities (Details) - shares shares in Thousands	12 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 30, 2018
Under option, balance (in shares)	809	1,100	1,271
Exercised (in shares)	0	(93)	(131)
Canceled (in shares)	(396)	(198)	(40)
Under option, balance (in shares)	413	809	1,100
Exercisable, end of year (in shares)	413	809	1,100

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Number of options outstanding, including both vested and non-vested options.

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Number of share options (or share units) exercised during the current period.

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