Note 8 - Accrued Liabilities (Details) - Summary of Current and Long-Term Accrued Liabilities (USD $) In Thousands, unless otherwise specified	Aug. 30, 2014	Aug. 31, 2013
Summary of Current and Long-Term Accrued Liabilities [Abstract]
Payroll and benefit related	$ 48,978	$ 47,361
Insurance related	37,683	36,095
Environmental related	5,046	5,158
Other	9,111	6,968
	100,818	95,582
Benefit related	23,760	19,719
Environmental related	14,800	14,522
Asset retirement obligations	11,675	10,796
	50,235	45,037
Total accrued liabilities	$ 151,053	$ 140,619