Financial Instruments - Outstanding Currency, Forward Exchange Contracts (Detail) (Foreign Currency Forward Contracts [Member], USD $) In Thousands, unless otherwise specified	Jul. 31, 2014
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	$ 504,870
Fair Market Value of foreign currency derivative sale contracts	499,739
Notional Amounts of foreign currency derivative purchase contracts	573,884
Fair Market Value of foreign currency derivative purchase contracts	568,474
Euro [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	379,824
Fair Market Value of foreign currency derivative sale contracts	374,283
Notional Amounts of foreign currency derivative purchase contracts	338,853
Fair Market Value of foreign currency derivative purchase contracts	334,180
British Pound [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	51,386
Fair Market Value of foreign currency derivative sale contracts	52,049
Notional Amounts of foreign currency derivative purchase contracts	68,286
Fair Market Value of foreign currency derivative purchase contracts	68,078
Japanese Yen [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	15,667
Fair Market Value of foreign currency derivative sale contracts	15,477
Notional Amounts of foreign currency derivative purchase contracts	9,161
Fair Market Value of foreign currency derivative purchase contracts	9,068
Australian Dollar [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	468
Fair Market Value of foreign currency derivative sale contracts	465
Notional Amounts of foreign currency derivative purchase contracts	9,018
Fair Market Value of foreign currency derivative purchase contracts	9,024
Hong Kong Dollar [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	53,195
Fair Market Value of foreign currency derivative sale contracts	53,202
Notional Amounts of foreign currency derivative purchase contracts	111,493
Fair Market Value of foreign currency derivative purchase contracts	111,508
Singapore Dollar [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	0
Fair Market Value of foreign currency derivative sale contracts	0
Notional Amounts of foreign currency derivative purchase contracts	10,447
Fair Market Value of foreign currency derivative purchase contracts	10,454
Others [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative sale contracts	4,330
Fair Market Value of foreign currency derivative sale contracts	4,263
Notional Amounts of foreign currency derivative purchase contracts	26,626
Fair Market Value of foreign currency derivative purchase contracts	$ 26,162