Employee Benefit and Retirement Plans (Reconciliation Of Benefit Obligations, Plan Assets, And Funded Status) (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Retirement Benefits [Abstract]
Projected benefit obligation at beginning of year	$ 168,788	$ 163,423
Interest cost	5,974	6,269	$ 5,727
Acturial (gains) and losses	22,293	4,850
Benefits paid	(5,871)	(5,754)
Projected benefit obligation at end of year	191,184	168,788	163,423
Fair value of plan assets at beginning of year	169,471	156,463
Actual return on plan assets	26,674	11,479
Company contributions	469	7,283
Benefits paid	(5,871)	(5,754)
Fair value of plan assets at end of year	190,743	169,471	$ 156,463
Funded status of the plan	$ (441)	$ 683

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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.

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