Fair Values of Derivative Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Aug. 31, 2012
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 3,552	$ 2,703
Designated as Hedging Instrument | Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	2,470	3,043
Designated as Hedging Instrument | Foreign Currency Forward Exchange Contracts | Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives		182
Designated as Hedging Instrument | Foreign Currency Forward Exchange Contracts | Accounts Receivable
Derivatives, Fair Value [Line Items]
Asset Derivatives	3,552	2,703
Designated as Hedging Instrument | Interest Rate Swap | Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	2,470	2,861
Not Designated as Hedging Instrument | Foreign Currency Forward Exchange Contracts | Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives		102
Not Designated as Hedging Instrument | Foreign Currency Forward Exchange Contracts | Accounts Receivable
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 530	$ 141