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Deferred Compensation And Retirement Plans (Reconciliation Of Benefit Obligation) (Parenthetical) (Detail) - CSV of COLI Contracts - USD ($) $ in Millions | Apr. 30, 2018 | Apr. 30, 2017
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Gross CSV | $ 186.8 | $ 180.3
Outstanding policy loans | 66.7 | 67.2
Deferred Compensation Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Gross CSV | 186.8 | 180.3
Outstanding policy loans | $ 66.7 | $ 67.2

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- Details
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- Details
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