Note 11 - Commitments and Contingencies (Details) - Anticipated Payments and Insurance Proceeds of Identified Environmental Remediation Liabilities (USD $) In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 25, 2012	Aug. 27, 2011
Anticipated Payments and Insurance Proceeds of Identified Environmental Remediation Liabilities [Abstract]
Estimated costs – current dollars	$ 5,317
Estimated costs – current dollars	2,620
Estimated costs – current dollars	1,887
Estimated costs – current dollars	865
Estimated costs – current dollars	797
Estimated costs – current dollars	12,421
Estimated costs – current dollars	23,907
Estimated insurance proceeds	(159)
Estimated insurance proceeds	(173)
Estimated insurance proceeds	(159)
Estimated insurance proceeds	(173)
Estimated insurance proceeds	(159)
Estimated insurance proceeds	(1,593)
Estimated insurance proceeds	(2,416)
Net anticipated costs	5,158
Net anticipated costs	2,447
Net anticipated costs	1,728
Net anticipated costs	692
Net anticipated costs	638
Net anticipated costs	10,828
Net anticipated costs	21,491
Effect of inflation	7,055
Effect of discounting	(8,866)
Balance as of August 31, 2013	$ 19,680	$ 20,020	$ 18,368