Summary Of Refranchisings and Franchisee Development (Number Of Restaurants Sold And Developed By Franchisees And Related Gains And Fees Recognized) (Details) - restaurant	4 Months Ended
Jan. 17, 2021	Jan. 19, 2020
Summary Of Refranchisings, Franchisee Development And Acquisitions [Abstract]
Number of Company-operated restaurants sold to franchisees	0	0

The number of franchises sold during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 952
-SubTopic 605
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68064525&loc=d3e68639-108044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 952
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109207840&loc=SL51750552-203207

Name:	us-gaap_SignificantChangesFranchisesSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration