Summary Of Refranchisings, Franchisee Development And Acquisitions (Number Of Restaurants Sold And Developed By Franchisees And Related Gains And Fees Recognized) (Details) $ in Thousands	4 Months Ended
Jan. 19, 2020 USD ($) restaurant	Jan. 20, 2019 USD ($) restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Abstract]
Number of new restaurants opened by franchisees	11	9
Number of franchised restaurants closed	(10)	(5)
Number of Company-operated restaurants sold to franchisees	0	0
Gains on the sale of company-operated restaurants \| $	$ (1,575)	$ (219)

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration