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Nature of Operations and Summary of Significant Accounting Policies (Summary of Number of Restaurants) (Details) - restaurant	Sep. 29, 2019	Sep. 30, 2018	Oct. 01, 2017
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	2,243	2,237	2,251
Company-operated
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	137	137	276
Franchise
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	2,106	2,100	1,975

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Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]

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Represents the number of restaurants.

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