Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Oct. 21, 2015	Aug. 29, 2015	Aug. 30, 2014	Aug. 31, 2013
Components Of Shareholders Equity [Line Items]
Preferred stock, shares authorized		5,000,000	5,000,000
Preferred stock, shares issued		0	0
Preferred stock, shares outstanding		0	0
Payment of special cash dividend		$ 185,403
Payments of regular cash dividends		98,828	$ 82,607	$ 75,860
Purchase of treasury stock		$ 33,414	$ 191,359	$ 3,773
Subsequent Event [Member]
Components Of Shareholders Equity [Line Items]
Dividend payout	$ 26,515
Special Dividend [Member] | Subsequent Event [Member]
Components Of Shareholders Equity [Line Items]
Dividend declared date		Oct. 21, 2015
Ordinary Dividend [Member] | Subsequent Event [Member]
Components Of Shareholders Equity [Line Items]
Dividend declared, per share	$ 0.43
Dividend payable date		Nov. 24, 2015
Dividend record date		Nov. 10, 2015
Class A Common Stock [Member]
Components Of Shareholders Equity [Line Items]
Common stock, voting rights		1
Class B Common Stock [Member]
Components Of Shareholders Equity [Line Items]
Common stock, voting rights		10
Class A Treasury Stock [Member]
Components Of Shareholders Equity [Line Items]
Number of shares authorized for repurchase		5,000,000
Maximum number of shares that may yet be repurchased		1,743,000
Treasury stock reissued to fund plan. shares		63,000	54,000
Class A common stock shares repurchased		444,000	2,370,000	52,000
Purchase of treasury stock		$ 33,414	$ 191,359	$ 3,773
Shares repurchased by the company for associates' tax withholding liability associated with share-based compensation		112,000	60,000