Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						4 Months Ended		12 Months Ended
	Sep. 06, 2016	Jun. 14, 2016	Mar. 22, 2016	Sep. 08, 2015	Jun. 16, 2015	Mar. 24, 2015	Dec. 27, 2016	Dec. 29, 2015	Dec. 27, 2016	Dec. 29, 2015	Dec. 30, 2014
Earnings Per Share [Abstract]
Net income	$ 786	$ 4,444	$ 5,411	$ (1,035)	$ 3,713	$ 5,394	$ 7,125	$ 7,926	$ 17,766	$ 15,998	$ 16,597
Shares:
Weighted average number of common shares outstanding	23,354,000	23,350,000	23,315,000	23,361,000	23,446,000	23,443,000	23,282,000	23,298,000	23,322,344	23,380,085	23,517,883
Dilutive shares									112,931	137,203	222,435
Total Diluted Shares	23,431,000	23,437,000	23,398,000	23,361,000	23,672,000	23,596,000	23,415,000	23,308,000	23,435,275	23,517,288	23,740,318
Basic earnings per common share	$ 0.03	$ 0.19	$ 0.23	$ (0.04)	$ 0.16	$ 0.23	$ 0.31	$ 0.34	$ 0.76	$ 0.68	$ 0.71
Diluted earnings per common share	$ 0.03	$ 0.19	$ 0.23	$ (0.04)	$ 0.16	$ 0.23	$ 0.30	$ 0.34	$ 0.76	$ 0.68	$ 0.70