Investment Income, Net (Schedule of Investment Income, Net) (Details) - USD ($) $ in Millions |
3 Months Ended | ||||
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Aug. 31, 2018 |
Aug. 31, 2017 |
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| Investment Income, Net [Abstract] | |||||
| Interest income on corporate funds | $ 3.2 | $ 2.9 | |||
| Interest expense | (0.9) | (0.8) | |||
| Investment income, net | $ 2.3 | $ 2.1 | [1] | ||
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The net amount of nonoperating interest income (expense). No definition available.
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- Definition The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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