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Income Taxes - Narrative (Details) - USD ($) $ in Thousands | 4 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 21, 2018 | Jan. 22, 2017 | Sep. 29, 2019 | Sep. 30, 2018
Income Tax Contingency [Line Items] |  |  |  |  |
Statutory income tax rate, percent |  | 28.60% | 38.60% |  |
Tax Cuts and Jobs Act of 2017, income tax expense (benefit) |  | $ 30,627 | $ 0 |  |
Income tax expense (benefit), continuing Operations, Adjustment of Deferred Tax (Asset) Liability |  | $ 30,700 |  |  |
Effective tax rates | [1] | 78.50% | 38.70% |  |
Forecast |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Statutory income tax rate, percent |  |  |  | 21.00% | 24.50%
Qdoba |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Tax Cuts and Jobs Act of 2017, income tax expense (benefit) |  | $ 2,300 |  |  |
[1] | (1)Percentages may not add due to rounding.

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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