Note 9 - Stock Compensation Plans - Option Activity and Transactions (Details) - $ / shares	12 Months Ended
	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Options issued (in shares)	0	0	0
Options outstanding (in shares)	0	10,000	20,000
Options outstanding (in shares)	10,000	20,000
Options outstanding, price (in dollars per share)	$ 14.39	$ 14.39
Options canceled or expired (in shares)	0	0	(5,000)
Options canceled or expired, price (in dollars per share)	$ 0		$ 11.86
Options exercised (in shares)	(10,000)	(10,000)	(10,000)
Options exercised, price (in dollars per share)	$ 14.39		$ 11.86
Exercised during year (in dollars per share)	(14.39)		(11.86)
Options outstanding, price (in dollars per share)	$ 0	$ 14.39	$ 14.39
Exercisable at end of year (in shares)	0	10,000	6,666
Weighted-average fair value of options granted during the year (in dollars per share)	$ 0	$ 0	$ 0
Minimum [Member]
Options issued (in shares)	0	0
Options outstanding, price (in dollars per share)	$ 14.39	$ 14.39	14.39
Options canceled or expired, price (in dollars per share)		0
Options exercised, price (in dollars per share)		14.39
Exercised during year (in dollars per share)		(14.39)
Options outstanding, price (in dollars per share)		$ 14.39	$ 14.39
Maximum [Member]
Options issued (in shares)			0
Options outstanding, price (in dollars per share)			$ 11.86
Incentive Stock Options [Member]
Options issued (in shares)	0	0	0
Options outstanding (in shares)	0	10,000	20,000
Options outstanding (in shares)	10,000	20,000
Director Stock Options [Member]
Options issued (in shares)	0	0	0
Options outstanding (in shares)	0	0	0
Options outstanding (in shares)	0	0