INCOME TAXES (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Apr. 30, 2019
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 148.7	$ 178.1	$ 185.1
Gross unrecognized tax benefits increase (decrease)	(36.4)	(8.0)
Change in tax benefits that are reasonably possible	14.9
Discrete income tax benefit	$ 27.7	$ 8.9
Effective tax rate	29.20%	25.40%
Increase in effective tax rate from discrete item, percent	4.30%	1.50%

Effective Income Tax Rate Reconciliation, Discrete Adjustments, Amount

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Effective Income Tax Rate Reconciliation, Effect of Discrete Items, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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