Impact of Derivatives for Foreign Currency Risk and Not Designated as Hedging Instruments on Earnings (Detail) (Forward foreign exchange contracts, Cost of revenue, USD $) In Thousands, unless otherwise specified	6 Months Ended
	Feb. 28, 2013	Feb. 29, 2012
Forward foreign exchange contracts | Cost of revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ (11,020)	$ 2,815