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, 2020	May 31, 2019	May 31, 2020	May 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ (7,769)	$ (2,272)	$ (9,973)	$ (6,702)
Gain (loss) reclassified accumulated OCI income	(2,494)	(392)	(3,131)	(1,944)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	549	280	1,255	1,836
Foreign Exchange Forward \| Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	154		60	495
Foreign Exchange Forward \| Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	(599)	330	164	(16)
Gain (loss) reclassified accumulated OCI income	(485)	(68)	(584)	(735)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	138	264	781	1,164
Foreign Exchange Forward \| Cost Of Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	(2,015)	102	(2,198)	(293)
Gain (loss) reclassified accumulated OCI income	(1,226)	(181)	(1,228)	(771)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	130	179	474	857
Interest rate swap contracts \| Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	(5,155)	(2,704)	(7,939)	(6,393)
Gain (loss) reclassified accumulated OCI income	(783)	(143)	$ (1,319)	(438)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	$ 281	$ (163)		$ (185)

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

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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.

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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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