Note 7 - Employee Benefit Plans (Details) - Weighted Average Assumptions Used in Calculating the Company's Net Periodic Service Cost	12 Months Ended
Aug. 29, 2015	Aug. 30, 2014	Aug. 31, 2013
Pension Plan [Member]
Note 7 - Employee Benefit Plans (Details) - Weighted Average Assumptions Used in Calculating the Company's Net Periodic Service Cost [Line Items]
Discount rate	3.60%	4.30%	3.30%
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) - Weighted Average Assumptions Used in Calculating the Company's Net Periodic Service Cost [Line Items]
Discount rate	3.80%	4.60%	3.60%
Expected return on plan assets
Rate of compensation increase	5.00%	5.00%	5.00%

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- Definition

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=58740216&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=58740216&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

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

-URI http://asc.fasb.org/extlink&oid=6512046

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=58740216&loc=d3e1928-114920

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