Deferred Compensation and Retirement Plans - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 31, 2022	Apr. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Increase in market value of the underlying COLI investments			$ 3,947	$ 4,890
Decrease in the fair value of marketable securities	$ 13,800	$ 9,700	1,000	9,700
CSV of COLI Contracts
Defined Benefit Plan Disclosure [Line Items]
Increase in market value of the underlying COLI investments	2,000	2,900	3,900	4,900
Deferred Compensation Plan | CSV of COLI Contracts
Defined Benefit Plan Disclosure [Line Items]
Gross CSV	279,200		279,200		$ 275,100
Outstanding policy loans	77,100		$ 77,100		$ 77,100
Executive Capital Accumulation Plan
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation arrangement vesting period			5 years
Compensation expense (reduction)	(12,300)	(9,500)		(8,600)
Decrease in the fair value of marketable securities	$ 13,800	$ 9,700		$ 9,700
Executive Capital Accumulation Plan | Minimum
Defined Benefit Plan Disclosure [Line Items]
Option to receive employee benefits by quarterly installments periods			1 year
Executive Capital Accumulation Plan | Maximum
Defined Benefit Plan Disclosure [Line Items]
Option to receive employee benefits by quarterly installments periods			15 years