Income Taxes - Narrative (Details) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
		Jul. 08, 2018	Jul. 09, 2017	Jul. 08, 2018	Jul. 09, 2017	Sep. 29, 2019	Sep. 30, 2018
Income Tax Contingency [Line Items]
Statutory income tax rate, percent		28.60%	37.00%	28.90%	37.90%
Tax Cuts and Jobs Act of 2017, income tax expense (benefit)		$ 878,000	$ 0	$ 32,082,000	$ 0
Income tax expense (benefit), continuing Operations, Adjustment of Deferred Tax (Asset) Liability				$ 30,800,000
Effective tax rates	[1]	26.50%	32.10%	46.90%	36.50%
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)		$ 0		$ 2,300,000

[1] (1)Percentages may not add due to rounding.