Fair Value Measurement (Schedule Of Financial Assets And Liabilities Measured At Fair Value On Recurring Basis) (Details) - Fair Value Measurements Level 2 [Member] - USD ($) $ in Thousands	Mar. 21, 2017	Dec. 27, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan investments (included in Other assets)	$ 15,501	$ 15,054
Deferred compensation plan liabilities (included in Other liabilities)	$ 13,684	$ 15,212

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_DeferredCompensationPlanAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant