Deferred Compensation and Retirement Plans - Reconciliation of Fair Value of Plan Assets (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Apr. 30, 2020 |
Apr. 30, 2019 |
Apr. 30, 2018 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Current liability | $ 19,143 | $ 17,818 | |
| Non-current liability | 289,136 | 257,635 | |
| Total benefit obligation | 308,279 | 275,453 | |
| Medical and Life Insurance plan | Hay Group | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Benefit obligation, beginning of year | 7,310 | 7,157 | |
| Interest cost | 227 | 243 | $ 369 |
| Actuarial loss | 458 | 520 | |
| Benefits paid | (468) | (610) | |
| Benefit obligation, end of year | 7,527 | 7,310 | $ 7,157 |
| Current liability | 666 | 643 | |
| Non-current liability | 6,861 | 6,667 | |
| Total benefit obligation | $ 7,527 | $ 7,310 | |
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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