Note 1 - Summary of Significant Accounting Policies (Details) - Summary of Earnings Per Share, Diluted, 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, Diluted, by Common Class, Including Two Class Method [Line Items]
Earnings to common shareholders									$ 119,925	$ 116,685	$ 94,989
Add: Undistributed earnings allocated to unvested participating shares									1,339	1,810	1,664
Less: Undistributed earnings reallocated to unvested participating shares									(1,267)	(1,712)	(1,579)
Diluted EPS – Common Stock	28,631	30,637	25,326	34,031	30,178	28,307	26,196	30,244	118,626	114,927	93,358
Diluted EPS – Common Stock (in Shares)	20,007	19,977	19,924	19,891	19,882	19,820	19,747	19,693	19,939	19,789	19,616
Diluted EPS – Common Stock (in Dollars per share)	$ 1.43	$ 1.53	$ 1.27	$ 1.71	$ 1.52	$ 1.43	$ 1.33	$ 1.54	$ 5.95	$ 5.81	$ 4.76
Share-Based Awards (in Shares)									148	148	91
Common Class A [Member]
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Earnings to common shareholders	22,876	24,493	20,267	27,208	24,123	22,638	20,963	24,191	94,849	91,916	74,643
Common shares (in Shares)	15,113	15,102	15,077	15,029	15,017	14,993	14,962	14,925	15,080	14,975	14,882
EPS (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, Diluted, by Common Class, Including Two Class Method [Line Items]
Earnings to common shareholders	$ 5,742	$ 6,127	$ 5,041	$ 6,798	$ 6,033	$ 5,647	$ 5,209	$ 6,025	$ 23,705	$ 22,913	$ 18,630
Common shares (in Shares)	4,741	4,722	4,687	4,693	4,694	4,675	4,647	4,647	4,711	4,666	4,643
EPS (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