Derivative Instruments - Additional Information (Detail)	6 Months Ended
	Feb. 28, 2018 USD ($)
Foreign Exchange Contracts
Derivative [Line Items]
Aggregate derivative notional amount	$ 205,700,000
Amount reclassified to revenue or cost of revenue in the next 12 months	700,000
Interest rate swap contracts
Derivative [Line Items]
Aggregate derivative notional amount	$ 86,900,000
Maturity date	2020-03
Unrealized pre-tax gain (loss) that would be reclassified to interest expense in the next 12 months	$ 400,000