Derivatives and Hedging Activities - Fair Values of Derivative Instruments in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jan. 31, 2018	Jul. 31, 2017
Designated as hedging instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 377	$ 1,067
Liability Derivatives	56,846	54,849
Designated as hedging instruments [Member] | Cash flow hedging | Foreign exchange contract [Member] | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	377	1,067
Designated as hedging instruments [Member] | Cash flow hedging | Foreign exchange contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	1,046	1,569
Designated as hedging instruments [Member] | Net investment hedging [Member] | Foreign currency denominated debt [Member] | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	0
Designated as hedging instruments [Member] | Net investment hedging [Member] | Foreign currency denominated debt [Member] | Long term obligations less current maturities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	55,800	53,280
Not designated as hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	2	287
Liability Derivatives	8	7
Not designated as hedging Instruments [Member] | Foreign exchange contract [Member] | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	2	287
Not designated as hedging Instruments [Member] | Foreign exchange contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 8	$ 7