Fair Value Measurement (Schedule Of Financial Assets And Liabilities Measured At Fair Value On Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 27, 2016	Dec. 29, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan investments	$ 15,054	$ 13,955
Deferred compensation plan liabilities	(15,212)	(14,083)
Fair Value Measurements Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan investments	15,054	13,955
Deferred compensation plan liabilities	$ (15,212)	$ (14,083)