Note 1 - Summary of Significant Accounting Policies (Details) - Summary of Earnings Per Share, Basic, Two Class Method (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Aug. 30, 2014	May 31, 2014	Mar. 01, 2014	Nov. 30, 2013	Aug. 31, 2013	May 25, 2013	Feb. 23, 2013	Nov. 24, 2012	Aug. 30, 2014	Aug. 31, 2013	Aug. 25, 2012
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income available to shareholders									$ 119,925	$ 116,685	$ 94,989
Weighted average number of shares for Basic:
Weignted average number of shares for Basic (in Shares)									20,040	19,986	19,916
Common Class A [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income available to shareholders	22,876	24,493	20,267	27,208	24,123	22,638	20,963	24,191	94,849	91,916	74,643
Weighted average number of shares for Basic:
Weignted average number of shares for Basic (in Shares)									15,080	14,975	14,882
Earnings per share for Basic:
Earnings per share for Basic (in Dollars per share)	$ 1.51	$ 1.62	$ 1.34	$ 1.81	$ 1.61	$ 1.51	$ 1.40	$ 1.62	$ 6.29	$ 6.14	$ 5.02
Common Class B [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income available to shareholders	5,742	6,127	5,041	6,798	6,033	5,647	5,209	6,025	23,705	22,913	18,630
Weighted average number of shares for Basic:
Weignted average number of shares for Basic (in Shares)									4,711	4,666	4,643
Earnings per share for Basic:
Earnings per share for Basic (in Dollars per share)	$ 1.21	$ 1.30	$ 1.08	$ 1.45	$ 1.29	$ 1.21	$ 1.12	$ 1.30	$ 5.03	$ 4.91	$ 4.01
Unvested Participating Shares [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income available to shareholders									$ 1,371	$ 1,856	$ 1,716
Weighted average number of shares for Basic:
Weignted average number of shares for Basic (in Shares)									249	345	391