Derivative Instruments - Effect of Derivative Instruments on Statements of Operations (Detail) - Cash Flow Hedging - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	$ (2)	$ (4,902)	$ (750)	$ (2,204)
Gain (loss) reclassified from accumulated OCI into income	(1,648)	(229)	(3,266)	(637)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	214	284	367	706
Foreign Exchange Forward \| Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivatives	(9)	(165)	(132)	(94)
Foreign Exchange Forward \| Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	(602)	190	(1,612)	763
Gain (loss) reclassified from accumulated OCI into income	(377)	67	(623)	(99)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	154	190	302	643
Foreign Exchange Forward \| Cost Of Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	(234)	411	(295)	(183)
Gain (loss) reclassified from accumulated OCI into income	(8)	73	(49)	(2)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)	60	210	65	344
Interest rate swap contracts \| Interest and Foreign Exchange
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in OCI on derivatives	834	(5,503)	1,157	(2,784)
Gain (loss) reclassified from accumulated OCI into income	$ (1,263)	(369)	$ (2,594)	(536)
Gain (loss) recognized on derivative (amount excluded from effectiveness testing)		$ (116)		$ (281)

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.

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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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