Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 25, 2012	Aug. 27, 2011	Aug. 28, 2010
Statement of Stockholders' Equity [Abstract]
Prior service cost and actuarial (loss), tax	$ (5,298)	$ (1,166)	$ (1,260)
Unrealized appreciation (depreciation) of investments, tax	(189)	(3)	128
Plan amendment, tax	$ 1,729

Tax effect, net of reclassification adjustments, of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i-k)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580

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