Derivative Financial Instruments (Details 1) - Cash Flow Hedging [Member] - Interest Rate Contract [Member] - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recognized in other comprehensive income (loss)	$ (190.7)	$ (49.1)	$ 2.7
Change in accumulated other comprehensive income (loss)	(188.6)	(48.7)	3.2
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated other comprehensive	$ (2.1)	$ (0.4)	$ (0.5)

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Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

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-Publisher FASB
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-SubTopic 10
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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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