Note 6 - Employee Benefit Plans - Performance Based Stock Unit Activity Under Share-based Compensation Plans (Details) - Equity Based Performance Stock Units [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Outstanding, beginning of year, units (in shares)	384	425	364
Outstanding, beginning of year, wt. avg. (in dollars per share)	$ 22.22	$ 15.51	$ 18.72
Granted, units (in shares)	151	93	200
Granted, wt. avg. (in dollars per share)	$ 33.22	$ 51.43	$ 13.18
Released, units (in shares)	(55)	(125)	(39)
Released, wt. avg. (in dollars per share)	$ 14.11	$ 21.77	$ 21.40
Cancelled, units (in shares)	(77)	(9)	(100)
Cancelled, wt. avg. (in dollars per share)	$ 15.94	$ 14.04	$ 20.25
Outstanding, end of year, units (in shares)	403	384	425
Outstanding, end of year, wt. avg. (in dollars per share)	$ 28.64	$ 22.22	$ 15.51