Deferred Compensation and Retirement Plans - Schedule of Components Of Net Periodic Benefit Costs (Detail) - Medical And Life Insurance Benefits - Hay Group - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 0
Interest cost	219	217	195
Net prior service credit amortization	(308)	(308)	(308)
Amortization of actuarial gain	(119)	(83)	(74)
Net periodic benefit cost	$ (208)	$ (174)	$ (187)