Acquisition - Additional Information (Detail) - USD ($)			4 Months Ended	12 Months Ended
	Sep. 27, 2014	Dec. 19, 2012	Aug. 29, 2015	Aug. 30, 2014	Aug. 31, 2013
Business Acquisition [Line Items]
Goodwill		$ 83,400,000	$ 391,887,000	$ 367,829,000	$ 367,829,000
Purchase price allocation, intangible assets		58,700,000
Goodwill impairment charge			$ 0	$ 0	18,300,000
Trade name, impairment charge					$ 4,100,000
Interamerican Motor Corporation [Member]
Business Acquisition [Line Items]
Acquisition of outstanding stock	$ 75,700,000
Goodwill	24,100,000
Purchase price allocation, intangible assets	$ 3,600,000
AutoAnything [Member]
Business Acquisition [Line Items]
Acquisition of outstanding stock		$ 116,100,000