Stock-Based Employee Compensation (Summary Of Stock Option Activity) (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 21, 2017 USD ($) $ / shares shares
Stock-Based Employee Compensation [Abstract]
Outstanding at beginning of period, Shares | shares	927,675
Exercised, Shares | shares	(30,100)
Forfeited, Shares | shares	(31,125)
Outstanding at end of period, Shares | shares	866,450
Options exercisable at end of period, Shares | shares	735,075
Outstanding at beginning of period, Weighted average exercise price | $ / shares	$ 18.33
Exercised, Weighted average exercise price | $ / shares	13.00
Forfeited, Weighted average exercise price | $ / shares	21.00
Outstanding at end of period, Weighted average exercise price | $ / shares	18.42
Options exercisable at end of period, Weighted average exercise price | $ / shares	$ 17.95
Outstanding at end of period, Weighted average Remaining Contractual Term	5 years 6 months
Options exercisable at end of period, Weighted average Remaining Contractual Term	5 years 3 months 18 days
Outstanding at end of period, Aggregate Intrinsic Value | $	$ 1,314
Options exercisable at end of period, Aggregate Intrinsic Value | $	$ 1,308