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Deferred Compensation And Retirement Plans - Reconciliation Of Benefit Obligation (Parenthetical) (Detail) - CSV of COLI Contracts - USD ($) $ in Millions | Apr. 30, 2021 | Apr. 30, 2020
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Outstanding policy loans | $ 80.0 | $ 92.3
Deferred Compensation Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Gross CSV | 241.3 | 238.7
Outstanding policy loans | $ 80.0 | $ 92.3

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- Definition Cash Surrender Value of Life Insurance Gross + References No definition available. + Details
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Period Type: | instant

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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. + References No definition available. + Details
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- Details
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- Details
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