Litigation - Additional Information (Detail)	12 Months Ended
	Aug. 25, 2012
Loss Contingencies [Line Items]
Site contingency, recovery from third party of environmental remediation cost	In 2004, the Company acquired a store site in Mount Ephraim, New Jersey that had previously been the site of a gasoline service station and contained evidence of groundwater contamination. Upon acquisition, the Company voluntarily reported the groundwater contamination issue to the New Jersey Department of Environmental Protection and entered into a Voluntary Remediation Agreement providing for the remediation of the contamination associated with the property. The Company has conducted and paid for (at an immaterial cost to the Company) remediation of visible contamination on the property and is investigating and will be addressing potential vapor intrusion impacts in downgradient residences and businesses. Pursuant to the Voluntary Remediation Agreement, upon completion of all remediation required by the agreement, the Company is eligible to be reimbursed up to 75 percent of its remediation costs by the State of New Jersey. Although the aggregate amount of additional costs that the Company may incur pursuant to the Voluntary Remediation Agreement cannot currently be ascertained, the Company does not currently believe that fulfillment of its obligations under the agreement will result in costs that are material to its financial condition, results of operations or cash flow.
Reimbursable remediation costs	75.00%