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Derivative Instruments - Effect of Derivative Instruments on Statements of Income (Detail) - Cash Flow Hedging - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2021	May 31, 2020	May 31, 2021	May 31, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ 252	$ (7,769)	$ (498)	$ (9,973)
Gain (loss) reclassified from accumulated OCI into income	(1,853)	(2,494)	(5,119)	(3,131)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	197	549	564	1,255
Foreign Exchange Forward | Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	95	154	(37)	60
Foreign Exchange Forward | Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	494	(599)	(1,118)	164
Gain (loss) reclassified from accumulated OCI into income	(522)	(485)	(1,145)	(584)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	165	138	467	781
Foreign Exchange Forward | Cost Of Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	273	(2,015)	(22)	(2,198)
Gain (loss) reclassified from accumulated OCI into income	(24)	(1,226)	(73)	(1,228)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	32	130	97	474
Interest rate swap contracts | Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	(515)	(5,155)	642	(7,939)
Gain (loss) reclassified from accumulated OCI into income	$ (1,307)	(783)	$ (3,901)	$ (1,319)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)		$ 281

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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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

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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

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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