Related Parties - Affiliated Rents Paid for Restaurant Property Lease (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 14, 2018	Mar. 15, 2017	Mar. 14, 2018	Mar. 15, 2017
Related Party Transaction [Line Items]
Selling, general and administrative expenses	$ 9,188	$ 9,008	$ 20,712	$ 22,767
Affiliated costs incurred as a percentage of relative total Company costs	0.42%	0.38%	0.42%	0.38%
Affiliated Cost Incurred
Related Party Transaction [Line Items]
Capital expenditures			$ 2	$ 4
Other operating expenses, occupancy costs and opening costs, including property leases			305	288
Total			307	292
Relative Total Company Costs
Related Party Transaction [Line Items]
Selling, general and administrative expenses			20,712	22,767
Capital expenditures			8,030	7,962
Other operating expenses, occupancy costs and opening costs, including property leases			45,232	45,506
Total			$ 73,974	$ 76,235