Note 6 - Employee Benefit Plans - Stock Options Outstanding and Exercisable (Details) - $ / shares shares in Thousands	12 Months Ended
Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Options outstanding, weighted average exercise price (in dollars per share)	$ 9.44	$ 10.01	$ 10.27	$ 10.22
Options outstanding, number (in shares)	12	262	363	405
Options outstanding, weighted average remaining life (Year)	1 year 3 months 18 days
Options exercisable, number (in shares)	12
Options exercisable, weighted average exercise price (in dollars per share)	$ 9.44

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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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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