Derivative Financial Instruments - Outstanding Currency, Forward Exchange Contracts (Detail) - Foreign Currency Forward Contracts [Member] - USD ($) $ in Thousands	Jul. 31, 2020	Jul. 31, 2019
Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	$ 205,754	$ 278,813
Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	457,903	408,006
Euro [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	108,856	219,910
Euro [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	207,198	90,043
British Pound [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	18,861	20,542
British Pound [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	60,397	45,955
Japanese Yen [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	15,815	32,560
Japanese Yen [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	32,009	48,670
Australian Dollar [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	174	350
Australian Dollar [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	7,682	7,683
Hong Kong Dollar [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	56,279	1,209
Hong Kong Dollar [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	74,714	136,818
Singapore Dollar [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	1,357	782
Singapore Dollar [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	15,982	15,449
Others [Member] | Sell [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	4,412	3,460
Others [Member] | Buy [Member]
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	$ 59,921	$ 63,388