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Summary of Refranchisings, Franchisee Development and Acquisitions (Purchase Price Allocations on Franchise Acquisitions) (Details) - restaurant | 1 Months Ended | 12 Months Ended
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Jan. 31, 2017 | Sep. 29, 2019 | Sep. 30, 2018 | Oct. 01, 2017
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Number of restaurants acquired from franchisees |  | 0 | 0 | 50
Number of restaurants closed |  |  |  | 3
Number of restaurants sold to franchisees |  | 0 | 135 | 178
2017 Reacquired Franchise Restaurants |  |  |  |
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Number of restaurants closed |  |  |  | 8
Number of restaurants sold to franchisees |  |  |  | 42
Underperforming Franchisee |  |  |  |
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Number of restaurants acquired from franchisees |  |  |  | 31
Obtained Judgment |  |  |  |
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Number of restaurants acquired from franchisees | 19 |  |  |

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- Definition The number of franchises purchased during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 952 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109207840&loc=SL51750552-203207 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 952 -SubTopic 605 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68064525&loc=d3e68639-108044 + Details
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- Definition The number of franchises sold during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period. + References 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 + Details
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