Interest rate stated in the contractual debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Basic and Diluted Earnings Per Share (Parenthetical) (Detail) (2% Convertible Notes)	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010	Nov. 30, 2003
2% Convertible Notes
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Debt instrument, interest rate	2.00%	2.00%	2.00%	2.00%