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Summary of Refranchisings and Franchise Acquisition (Narrative) (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 28, 2025 USD ($) | Jul. 06, 2025 USD ($) | Sep. 28, 2025 USD ($) restaurant | Sep. 29, 2024 USD ($) restaurant
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Goodwill, acquired during period |  |  | $ 6,326 |
Del Taco |  |  |  |
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Restaurants acquired from Del Taco franchisees | restaurant |  |  | 18 | 10
Goodwill, acquired during period | $ 6,300 | $ 6,300 | $ 6,326 |
Del Taco |  |  |  |
Summary Of Refranchisings, Franchisee Development And Acquisitions [Line Items] |  |  |  |
Purchase price |  |  | 7,193 | $ 86
Goodwill, acquired during period |  |  | $ 6,326 | $ 0

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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-8 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 41 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479303/805-10-55-41 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 + Details
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 24 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482548/350-20-55-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482573/350-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-4 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 + Details
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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 -Topic 952 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482948/952-10-50-1 + Details
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