Derivative Financial Instruments - Outstanding Currency, Forward Exchange Contracts (Detail) - Foreign Currency Forward Contracts - USD ($) $ in Thousands	Jan. 31, 2021	Jan. 31, 2020
Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	$ 238,626	$ 292,257
Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	569,636	476,416
Euro | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	122,414	227,292
Euro | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	270,516	118,275
British pound | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	20,206	18,934
British pound | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	60,579	54,818
Japanese yen | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	25,011	37,429
Japanese yen | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	42,370	58,672
Australian dollar | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	193	345
Australian dollar | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	9,255	7,817
Hong Kong dollar | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	60,949	643
Hong Kong dollar | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	88,915	152,452
Singapore dollar | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	204	1,109
Singapore dollar | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	16,983	15,987
Others | Sell
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	9,649	6,505
Others | Buy
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	$ 81,018	$ 68,395