Note 6 - Employee Benefit Plans - Stock Option Activity Under Share-based Compensation Plans (Details) - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Outstanding and exercisable balance (in shares)	12	262	363
Outstanding and exercisable, weighted average exercise price, balance (in dollars per share)	$ 9.44	$ 10.01	$ 10.27
Exercised, outstanding and exercisable (in shares)	(12)	(250)	(101)
Exercised, weighted average exercise price (in dollars per share)	$ 9.44	$ 10.03	$ 10.95
Outstanding and exercisable balance (in shares)	0	12	262
Outstanding and exercisable, weighted average exercise price, balance (in dollars per share)	$ 0	$ 9.44	$ 10.01

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 price at which option holders acquired shares when converting their stock options into shares.

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