Effect of Derivative Instruments on Statements of Income (Detail) - USD ($) $ in Thousands	9 Months Ended
May. 31, 2015	May. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	$ 47	$ 230
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives (effective portion)	(773)	277
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(831)	(700)
Gain Recognized on Derivative (Ineffective portion and Amount Excluded from Effectiveness Testing)	1,024	684
Foreign Exchange Forward \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives (effective portion)	1,867	1,558
Foreign Exchange Forward \| Interest and Foreign Exchange \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	(22)	230
Gain Recognized on Derivative (Ineffective portion and Amount Excluded from Effectiveness Testing)	1,024	684
Foreign Exchange Forward \| Sales \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	518	575
Interest rate swap contracts \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives (effective portion)	(2,640)	(1,281)
Interest rate swap contracts \| Interest and Foreign Exchange \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	69
Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ (1,349)	$ (1,275)

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

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-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

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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

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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

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-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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

-Publisher FASB

-Name Accounting Standards Codification

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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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