Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Earnings Per Share [Abstract]
Net income available to common stockholders	$ 838	$ 903	$ 827
Share data (in thousands):
Basic average common shares outstanding (shares)	478,879	478,527	477,765
Dilutive effect of stock-based awards (shares)	1,686	2,150	2,644
Diluted average common shares outstanding (shares)	480,565	480,677	480,409
Basic earnings per share (dollars per share)	$ 1.75	$ 1.89	$ 1.73
Diluted earnings per share (dollars per share)	$ 1.74	$ 1.88	$ 1.72
Antidilutive common stock-based awards excluded from calculation of diluted earnings per share (shares)	691	234	301