Effect of Derivative Instruments on Statements of Income (Detail) - Cash Flow Hedging - USD ($) $ in Thousands	9 Months Ended
May 31, 2016	May 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	$ (157)	$ 47
Gain (loss) recognized in OCI on derivatives (effective portion)	(8,623)	(773)
Gain (loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(2,450)	(831)
Gain (loss) Recognized on Derivative (Ineffective portion and Amount Excluded from Effectiveness Testing)	2,660	1,024
Foreign Exchange Forward
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives (effective portion)	(5,430)	1,867
Foreign Exchange Forward \| Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	(245)	(22)
Foreign Exchange Forward \| Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(835)	518
Gain (loss) Recognized on Derivative (Ineffective portion and Amount Excluded from Effectiveness Testing)	2,572	1,024
Foreign Exchange Forward \| Cost Of Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives (effective portion)	(919)
Gain (loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(412)
Gain (loss) Recognized on Derivative (Ineffective portion and Amount Excluded from Effectiveness Testing)	88
Interest rate swap contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives (effective portion)	(2,274)	(2,640)
Interest rate swap contracts \| Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	88	69
Gain (loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ (1,203)	$ (1,349)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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