Derivative financial instruments - Outstanding Currency, Forward Exchange Contracts (Detail) - USD ($) $ in Thousands	Apr. 30, 2024	Apr. 30, 2023
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	$ 730,716
Foreign Currency Forward Contracts | Notional Sell Amounts
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	184,014	$ 162,822
Foreign Currency Forward Contracts | Notional Sell Amounts | Euro
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	137,867	109,595
Foreign Currency Forward Contracts | Notional Sell Amounts | British pound
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	17,490	28,614
Foreign Currency Forward Contracts | Notional Sell Amounts | Mexican Peso
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	927	871
Foreign Currency Forward Contracts | Notional Sell Amounts | Japanese yen
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	18,665	21,619
Foreign Currency Forward Contracts | Notional Sell Amounts | Hong Kong dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	3,739	0
Foreign Currency Forward Contracts | Notional Sell Amounts | Australian dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	331	0
Foreign Currency Forward Contracts | Notional Sell Amounts | Singapore dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	109	60
Foreign Currency Forward Contracts | Notional Sell Amounts | Taiwan Dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	0	0
Foreign Currency Forward Contracts | Notional Sell Amounts | Others
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	4,886	2,063
Foreign Currency Forward Contracts | Notional Sell Amounts
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	517,911	584,675
Foreign Currency Forward Contracts | Notional Sell Amounts | Euro
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	145,019	155,683
Foreign Currency Forward Contracts | Notional Sell Amounts | British pound
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	181,427	123,134
Foreign Currency Forward Contracts | Notional Sell Amounts | Mexican Peso
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	32,979	27,577
Foreign Currency Forward Contracts | Notional Sell Amounts | Japanese yen
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	27,588	26,700
Foreign Currency Forward Contracts | Notional Sell Amounts | Hong Kong dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	7,438	148,303
Foreign Currency Forward Contracts | Notional Sell Amounts | Australian dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	9,441	8,892
Foreign Currency Forward Contracts | Notional Sell Amounts | Singapore dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	19,867	19,759
Foreign Currency Forward Contracts | Notional Sell Amounts | Taiwan Dollar
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	8,000	8,000
Foreign Currency Forward Contracts | Notional Sell Amounts | Others
Derivative [Line Items]
Notional Amounts of foreign currency derivative contracts	$ 86,152	$ 66,627