Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	12 Months Ended
	Aug. 27, 2011	Aug. 28, 2010
Accounts receivable, allowance for doubtful accounts	$ 6,184	$ 5,489
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Class A treasury stock, shares	4,722,706	3,528,379
Class A Common Stock [Member]
Common stock, voting rights	one vote per share	one vote per share
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	51,123,180	48,380,376
Common stock, shares outstanding	46,400,474	44,851,997
Class B Common Stock [Member]
Common stock, voting rights	ten votes per share	ten votes per share
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	16,400,474	17,925,474
Common stock, shares outstanding	16,400,474	17,925,474