Quarterly Results of Operations (Parenthetical) (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2012		Aug. 31, 2011	Aug. 31, 2010
Quarterly Financial Information [Line Items]
Included outstanding warrants in the dilutive earnings per common share using the treasury stock method	1,101		2,401	1,622
Dilutive effect of notes	6,045	[1]
2018 Senior Notes
Quarterly Financial Information [Line Items]
Included outstanding warrants in the dilutive earnings per common share using the treasury stock method			2,300
Dilutive effect of notes			6,000
Debt issuance and interest costs, net of tax which were added back to net earnings			1.4

[1] In 2012, the dilutive effect of the 2018 Convertible notes are included as they were considered dilutive under the "if converted" method. In 2011, the dilutive effect of the 2.5 million weighted average shares underlying the 2018 Convertible Notes was excluded from the share calculation as it was the less dilutive of two approaches. See Note 2 - Summary of Significant Accounting Policies for a description of the Company's net earnings per share calculations. The dilutive effect of the 2026 Convertible notes was excluded from the share calculations as the stock price for each year presented was less than the initial conversion price of $48.05 and therefore considered anti-dilutive.