Nature of Operations and Summary of Significant Accounting Policies (Summary of Number of Restaurants) (Details) - restaurant	Oct. 03, 2021	Sep. 27, 2020	Sep. 29, 2019
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	2,218	2,241	2,243
Company-operated
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	163	144	137
Franchise
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items]
Number of restaurants	2,055	2,097	2,106