Pension - Projected benefit obligation and fair value of plan assets (Details) - Pension Plan $ in Thousands	12 Months Ended
Apr. 30, 2024 USD ($)
Pension
Defined Benefit Plan, Funding Status [Extensible List]	us-gaap:UnfundedPlanMember
Projected benefit obligation	$ (3,246)
Fair value of plan assets	3,636
Funded status of the plan	$ 390

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

Indicates status of funding for defined benefit plan designed to provide retirement benefits.

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+ Details