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Impairment and Other Charges, Net (Restructuring Costs) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 27, 2020 | Sep. 29, 2019 | Sep. 30, 2018
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 1,168 | $ 8,455 | $ 10,647
Employee severance and related costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 1,168 | 7,169 | 7,845
Strategic Alternatives Evaluation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 1,286 | 0
Qdoba Evaluation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 0 | 0 | 2,211
Other |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 0 | $ 0 | $ 591

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- Definition Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
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