Shareholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Aug. 31, 2013	Sep. 01, 2012	Aug. 27, 2011
Components Of Shareholders Equity [Line Items]
Increase in number of shares authorized for repurchase	5,000,000
Preferred stock, shares authorized	5,000,000	5,000,000
Dividend declared, per share	$ 0.33
Dividend payable date	Nov. 20, 2013
Dividend record date	Nov. 06, 2013
Dividend payable amount	$ 20,920
Shares repurchased, value	3,773	48,098	69,279
Class A Common Stock [Member]
Components Of Shareholders Equity [Line Items]
Shares repurchased, shares	52,000	671,000
Shares repurchased, value	$ 3,773	$ 48,098
Maximum number of shares that may yet be repurchased	4,384,000
Common stock voting rights per share	one vote per share	one vote per share
Common stock, number voting rights, per share	1	1
Treasury stock reissued to fund plan, shares	53,000	52,000
Class B Common Stock [Member]
Components Of Shareholders Equity [Line Items]
Common stock voting rights per share	ten votes per share	ten votes per share
Common stock, number voting rights, per share	10	10