Impact of Derivatives for Foreign Currency Risk and Designated as Hedging Instruments on Accumulated Other Comprehensive Income (Loss) and Earnings (Detail) (Forward foreign exchange contracts, USD $) In Thousands, unless otherwise specified	9 Months Ended
	May 31, 2012	May 31, 2011
Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	$ 3,053	$ 1,624
Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	2,117	1,506
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	(28)	344
Cost of revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	(563)	4,212
Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	1,677	1,423
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	(1,421)	345
Selling, general and administrative
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	(2,238)	1,033
Amount of Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(2,925)	482
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	$ 152	$ 200