Notes Payable (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	Aug. 31, 2011
Debt Instrument [Line Items]
Term loans	$ 132,553	$ 137,040
Other notes payable	257	90
Debt instrument face amount	430,534	434,854
Notes payable	428,079	429,140
2018 Senior Notes
Debt Instrument [Line Items]
Convertible senior notes	230,000	230,000
2026 Senior Notes
Debt Instrument [Line Items]
Convertible senior notes	67,724	67,724
Convertible Notes
Debt Instrument [Line Items]
Debt discount, net of accretion	$ (2,455)	$ (5,714)

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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-Name Accounting Principles Board Opinion (APB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Principles Board Opinion (APB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details