Derivatives and Hedging Activities - Fair Values of Derivative Instruments in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Apr. 30, 2019	Jul. 31, 2018
Designated as hedging instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 528	$ 1,076
Liability Derivatives	50,332	52,668
Designated as hedging instruments [Member] | Unrealized gain on cash flow hedges | Foreign exchange contract [Member] | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	528	1,076
Designated as hedging instruments [Member] | Unrealized gain on cash flow hedges | Foreign exchange contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	0	0
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	50,332	52,668
Not designated as hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	4	1
Liability Derivatives	10	3
Not designated as hedging Instruments [Member] | Foreign exchange contract [Member] | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	4	1
Not designated as hedging Instruments [Member] | Foreign exchange contract [Member] | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 10	$ 3