Share-Based Payments - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Nov. 23, 2013	Nov. 17, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Total share-based compensation expense related to stock options and share purchase plans	$ 9.3	$ 8.1
Stock options exercised - Shares	87,378	298,983
Stock options exercised - Weighted average exercise price	$ 193.24	$ 131.54
Stock options granted	341,785	349,560
Weighted average grant date fair value of options granted	$ 96.39	$ 98.09
Anti-dilutive shares excluded from the computation of earnings per share	0	368,580