Statements of Consolidated Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 779.5	$ 514.4	$ 1,338.6
Other comprehensive income (loss):
Foreign currency translation adjustments	(15.0)	(19.1)	26.6
Cash flow hedging derivative activity, net of tax	(145.2)	(37.5)	2.0
Pension and other postretirement benefit plans activity, net of tax	(36.7)	(9.0)	14.3
Available-for-sale securities activity, net of tax	(0.3)	0.5	(1.2)
Total Other Comprehensive Income (Loss)	(197.2)	(65.1)	41.7
Comprehensive Income	$ 582.3	$ 449.3	$ 1,380.3

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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