INCOME TAXES (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Apr. 30, 2020
Income Tax Disclosure [Abstract]
Discrete income tax expense (benefit)	$ 0.6	$ (8.3)
Effective tax rate	24.60%	29.60%
Increase in effective tax rate from discrete item, percent	0.50%	4.00%
Unrecognized tax benefits	$ 171.6	$ 179.2	$ 168.1
Gross unrecognized tax benefits increase (decrease)	3.5	$ (5.9)
Change in tax benefits that are reasonably possible	$ 12.1

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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