Note 7 - Employee Benefit Plans (Details) - The weighted average assumptions used in calculating the Company’s net periodic service cost	12 Months Ended
Aug. 31, 2013	Aug. 25, 2012	Aug. 27, 2011
Pension Plans [Member]
Note 7 - Employee Benefit Plans (Details) - The weighted average assumptions used in calculating the Company’s net periodic service cost [Line Items]
Discount rate	3.30%	4.60%	4.70%
Expected return on plan assets	3.90%	4.00%	4.00%
Rate of compensation increase
Supplemental Executive Retirement Plan [Member]
Note 7 - Employee Benefit Plans (Details) - The weighted average assumptions used in calculating the Company’s net periodic service cost [Line Items]
Discount rate	3.60%	4.90%	4.80%
Expected return on plan assets
Rate of compensation increase	5.00%	5.00%	5.00%

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Expected rate of compensation increases (for pay-related plans).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(2)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The interest rate used to adjust for the time value of money.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(1)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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