Deferred Compensation and Retirement Plans - Schedule of Reconciliation of Benefit Obligation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023
Change in benefit obligation:
Current liability	$ 48,618	$ 43,377
Non-current liability	477,770	440,396
Total liability	526,388	483,773
Medical And Life Insurance Benefits | Hay Group
Change in benefit obligation:
Balance, beginning of year	4,227	4,838
Interest cost	219	217	$ 195
Actuarial loss (gain)	214	(321)
Benefits paid	(472)	(507)
Balance, end of year	4,188	4,227	$ 4,838
Current liability	553	535
Non-current liability	3,635	3,692
Total liability	$ 4,188	$ 4,227