Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Nov. 30, 2012		Nov. 30, 2011
Earnings Per Share [Abstract]
Net income	$ 6,133		$ 5,499
Weighted average common shares outstanding - basic	57,672		61,693
Effect of dilutive employee stock options and unvested restricted stock units	413		44
Weighted average common shares - diluted	58,085		61,737
Net income per common share - basic	$ 0.11		$ 0.09
Net income per common share - diluted	$ 0.11		$ 0.09
Anti-dilutive securities excluded	4,567	[1]	7,146	[1]

[1] Anti-dilutive securities consist of stock options and unvested restricted stock units that were not included in the computation of diluted earnings per share because either the exercise price of the options was greater than the average market price of the common stock or the total assumed proceeds under the treasury stock method resulted in negative incremental shares and thus the inclusion would have been anti-dilutive.