Basis Of Presentation (Details) $ in Millions	4 Months Ended
Jan. 17, 2021 USD ($) restaurant segment	Jan. 19, 2020 USD ($) restaurant
Segment Reporting Information [Line Items]
Number of restaurants \| restaurant	2,237	2,244
Number of operating segments \| segment	1
Contractual obligation (percent)	5.00%
Marketing and advertising expense	$ 5.8	$ 5.3
Restricted cash	37.3
Uncollected Postponed Marketing Fees	6.6
Accounts Receivable [Member]
Segment Reporting Information [Line Items]
Uncollected Postponed Marketing Fees	4.4
Other Current Assets [Member]
Segment Reporting Information [Line Items]
Uncollected Postponed Marketing Fees	$ 2.2
Entity Operated Units
Segment Reporting Information [Line Items]
Number of restaurants \| restaurant	148	137
Franchised Units
Segment Reporting Information [Line Items]
Number of restaurants \| restaurant	2,089	2,107

ContractualContributionsTowardsAdvertisingCostsPercentageOfSales [Line Items]

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- Definition

Uncollected Postponed Marketing Fees

+ References

No definition available.

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- Definition

The total expense recognized in the period for promotion, public relations, and brand or product advertising.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Represents the number of restaurants.

+ References

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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