Financial Instruments - Financial Instruments and Balance Sheet Classification (Parenthetical) (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Apr. 30, 2020 |
Apr. 30, 2019 |
Apr. 30, 2018 |
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| Investment Holdings [Line Items] | |||
| Obligations for which assets are held in trust | $ 124.6 | $ 122.3 | |
| Gain (loss) on marketable securities | (1.8) | 8.1 | $ 10.3 |
| Unvested obligations under deferred compensation plans | 21.7 | 24.6 | |
| Mutual Funds | |||
| Investment Holdings [Line Items] | |||
| Gain (loss) on marketable securities | $ (1.8) | $ 8.1 | $ 10.3 |
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- Definition The amount of the liability included in the deferred compensation plans that is unvested and therefore the participants have not earned the right to. No definition available.
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- Definition Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 the liabilities for deferred compensation arrangements classified as other. No definition available.
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- Details
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