Impairment of Long-Lived Assets, Discontinued Operations, Property Held for Sale and Store Closings - Impairment Charges to Income from Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 14, 2018	Mar. 15, 2017	Mar. 14, 2018	Mar. 15, 2017
Discontinued Operations and Disposal Groups [Abstract]
Provision for asset impairments and restaurant closings	$ 1,407	$ 5,963	$ 2,252	$ 6,250
Net loss on disposition of property and equipment	$ (204)	$ 329	18	414
Total			$ 2,270	$ 6,664
Effect on EPS:
Basic (in dollars per share)			$ (0.08)	$ (0.23)
Assuming dilution (in dollars per share)			$ (0.08)	$ (0.23)