Derivatives and Hedging Activities - Fair Values of Derivative Instruments in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jul. 31, 2018	Jul. 31, 2017
Designated as hedging instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Asset Derivatives	$ 1,076	$ 1,067
Liability Derivatives	52,668	54,849
Not designated as hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Asset Derivatives	1	287
Liability Derivatives	3	7
Prepaid expenses and other current assets [Member] | Foreign exchange contract [Member] | Not designated as hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Asset Derivatives	1	287
Other current liabilities [Member] | Foreign exchange contract [Member] | Not designated as hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Liability Derivatives	3	7
Cash flow hedging [Member] | Prepaid expenses and other current assets [Member] | Foreign exchange contract [Member] | Designated as hedging instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Asset Derivatives	1,076	1,067
Cash flow hedging [Member] | Other current liabilities [Member] | Foreign exchange contract [Member] | Designated as hedging instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Liability Derivatives	0	1,569
Net investment hedging [Member] | Prepaid expenses and other current assets [Member] | Foreign currency denominated debt [Member] | Designated as hedging instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Asset Derivatives	0	0
Net investment hedging [Member] | Long term obligations less current maturities [Member] | Foreign currency denominated debt [Member] | Designated as hedging instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Liability Derivatives	$ 52,668	$ 53,280