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. 15, 2017	Mar. 09, 2016	Mar. 15, 2017	Mar. 09, 2016
Discontinued Operations and Disposal Groups [Abstract]
Provision for asset impairments and restaurant closings, net	$ 5,963	$ 37	$ 6,250	$ 37
Net loss (gain) on disposition of property and equipment	$ 329	$ (556)	414	(835)
Total			$ 6,664	$ (798)
Effect on EPS:
Basic (in dollars per share)			$ 0.23	$ 0.03
Assuming dilution (in dollars per share)			$ 0.23	$ 0.03