Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Aug. 29, 2015 USD ($) Store Branches Vendor Product shares	Aug. 30, 2014 USD ($) shares	Aug. 31, 2013 USD ($) shares	Aug. 25, 2012 USD ($)
Significant Accounting Policies [Line Items]
Number of stores with commercial sales program | Store	4,141
Cash and cash equivalents	$ 175,309,000	$ 124,485,000	$ 142,191,000	$ 103,093,000
Allowances for uncollectible accounts	5,900,000	2,900,000
Unrecorded adjustment for LIFO value in excess of replacement value	332,600,000	307,200,000
Impairment loss of long lived assets	0
Cumulative loss on currency translation recorded in accumulated other comprehensive loss	171,500,000	57,800,000
Deferred rent	$ 113,700,000	104,600,000
Measure of income tax benefit for uncertain income tax positions	More than 50%
Advertising expense, net of vendor promotional funds	$ 98,000,000	84,700,000	83,700,000
Vendor promotional funds, which reduced advertising expense	$ 22,000,000	28,400,000	$ 24,400,000
Limited warranty period, minimum period (Days)	30 days
Products accounted for total revenues	One class of similar products accounted for approximately 11 percent of the Company's total revenues,No other class of similar products accounted for 10 percent or more of total revenues
Products accounted for total purchases	One vendor supplied approximately 11 percent of the Company's total purchases.No other individual vendor provided more than 10 percent of total purchases
Senior Notes [Member]
Significant Accounting Policies [Line Items]
Unamortized debt issuance costs	$ 22,700,000	$ 20,700,000
Minimum [Member]
Significant Accounting Policies [Line Items]
Amortization of intangible assets	3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Amortization of intangible assets	10 years
Interamerican Motor Corporation [Member]
Significant Accounting Policies [Line Items]
Number of operating branches | Branches	20
Stock Options [Member]
Significant Accounting Policies [Line Items]
Anti-dilutive shares excluded from the computation of earnings per share | shares	1,640	1,000	8,600
Cash Equivalents [Member]
Significant Accounting Policies [Line Items]
Maturity period of investments	90 days or less
Settlement term of credit and debit card transaction	Less than 5 days
Credit and debit card receivables included within cash and cash equivalents	$ 45,100,000	$ 43,900,000
Product Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Number of class of similar products accounted for approximately 11% of the company's total revenues | Product	1
Product Concentration Risk [Member] | Sales Revenue, Net [Member]
Significant Accounting Policies [Line Items]
Concentration risk percentage	11.00%
Supplier Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Number of class of similar products accounted for approximately 11% of the company's total revenues | Vendor	1
Supplier Concentration Risk [Member] | Cost of Goods, Total [Member]
Significant Accounting Policies [Line Items]
Concentration risk percentage	11.00%
Buildings [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	40 years
Buildings [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	50 years
Building Improvements [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	5 years
Building Improvements [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	15 years
Equipment [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	3 years
Equipment [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives	10 years
Stores in the United States Including Puerto Rico [Member]
Significant Accounting Policies [Line Items]
Number of stores | Store	5,141
Brazil [Member]
Significant Accounting Policies [Line Items]
Number of stores | Store	7
Mexico [Member]
Significant Accounting Policies [Line Items]
Number of stores | Store	441
Foreign Countries [Member]
Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 64,900,000	$ 19,300,000