Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Aug. 25, 2012 Store	Aug. 27, 2011	Aug. 28, 2010
Significant Accounting Policies [Line Items]
Number of domestic stores in United States and Puerto Rico	4,685
Number of stores	5,006
Number of stores with commercial sales program	3,053
Allowances for uncollectible accounts	$ 2,400,000	$ 2,100,000
Unrecorded adjustment for LIFO value in excess of replacement value	270,400,000	253,300,000
Impairment loss of long lived assets	0
Impairment loss of goodwill	0
Goodwill	302,645,000	302,645,000
Cumulative loss on currency translation recorded in accumulated other comprehensive loss	50,267,000	36,401,000
Deferred rent	86,900,000	77,600,000
Measure of income tax benifit for uncertain income tax positions	More than 50%
Advertising expense, net of vendor promotional funds	74,700,000	71,500,000	65,500,000
Vendor promotional funds, which reduced advertising expense	19,700,000	23,200,000	19,600,000
Limited warranty period, minimum period (Days)	30 days
Products accounted for total revenues	one class of similar products accounted for 10 percent of the Company's total revenues
Products accounted for total purchases	One vendor supplied more than 10 percent of the Company's total purchases
Mexico [Member]
Significant Accounting Policies [Line Items]
Number of stores	321
Stock Options [Member]
Significant Accounting Policies [Line Items]
Anti-dilutive shares excluded from the computation of earnings per share	30,000
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 equilants	$ 34,000,000	$ 32,500,000
Buildings [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated maximum useful lives	40 years
Buildings [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated maximum useful lives	50 years
Building Improvements [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated maximum useful lives	5 years
Building Improvements [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated maximum useful lives	15 years
Equipment [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated maximum useful lives	3 years
Equipment [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated maximum useful lives	10 years