Foreign Currency Contracts - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2016	Apr. 30, 2015
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Foreign currency exchange gains (losses)	$ 137	$ (84)	$ (616)	$ 2,346
Foreign Exchange Contract
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	3,661		3,661
Foreign currency exchange gains (losses)	200	$ 500	100	$ (600)
Foreign Exchange Contract | Other Current Liabilities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative liability, notional amount	$ 100		$ 100