Option Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Aug. 31, 2012		Aug. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Available for Grant, Beginning Balance	9,164,425
Shares Available for Grant, Options cancelled	542,135
Shares Available for Grant, Options expired	(53,754)
Shares Available for Grant, Restricted stock awards	(4,768,887)	[1]
Shares Available for Grant, Ending Balance	4,883,919		9,164,425
Options Outstanding, beginning balance	10,473,033
Options Outstanding, options cancelled	(542,135)
Options Outstanding, options exercised	(1,252,957)
Options Outstanding, ending balance	8,677,941		10,473,033
Options Outstanding, exercisable ending balance	8,664,592
Aggregate Intrinsic Value, beginning balance	$ 4,029
Aggregate Intrinsic Value, ending balance	4,719		4,029
Aggregate Intrinsic Value, Exercisable ending balance	$ 4,602
Weighted-Average Exercise Price, beginning balance	$ 24.76
Weighted-Average Exercise Price, options cancelled	$ 26.59
Weighted-Average Exercise Price, options expired	$ 15.27
Weighted-Average Exercise Price, options exercised	$ 16.68
Weighted-Average Exercise Price, ending balance	$ 25.88		$ 24.76
Weighted-Average Exercise Price, exercisable ending balance	$ 25.90
Weighted-Average Remaining Contractual Life	2 years 10 months 24 days		3 years 8 months 12 days
Weighted-Average Remaining Contractual Life, Exercisable ending balance	2 years 10 months 24 days

[1] Represents the maximum number of shares that can be issued based on the achievement of certain performance criteria.