Derivatives and Hedging Activities - Additional Information (Detail) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2014 USD ($)	Oct. 31, 2013 USD ($)	Jul. 31, 2014 USD ($)	Oct. 31, 2014 GBP-denominated interco debt [Member] GBP (£)	May 13, 2010 Senior Unsecured Notes [Member] GBP (£)
Derivatives, Fair Value [Line Items]
Derivative maturity	18 months
Derivative, Notional Amount	$ 67,000		$ 104,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	601	(15)
Reclassification adjustment for losses (gains) included in net earnings	21	(90)
Total outstanding forward foreign exchange contracts	16,643
Net investment hedges to hedge portions of net investment				25,036	75,000
Amount Outstanding Forward Foreign Exchange Contracts Net Investment Hedge	4,700		5,300
Gain (Loss) on Derivative Used in Net Investment Hedge, Net of Tax	(295)	(244)
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ (841)	$ 1,447