Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Apr. 30, 2021 |
Apr. 30, 2020 |
Apr. 30, 2019 |
|
| Earnings Per Share [Abstract] | |||
| Net income available to common stockholders | $ 903 | $ 827 | $ 835 |
| Share data (in thousands): | |||
| Basic average common shares outstanding (shares) | 478,527 | 477,765 | 478,956 |
| Dilutive effect of stock-based awards (shares) | 2,150 | 2,644 | 3,111 |
| Diluted average common shares outstanding (shares) | 480,677 | 480,409 | 482,067 |
| Basic earnings per share (dollars per share) | $ 1.89 | $ 1.73 | $ 1.74 |
| Diluted earnings per share (dollars per share) | $ 1.88 | $ 1.72 | $ 1.73 |
| Antidilutive common stock-based awards excluded from calculation of diluted earnings per share (shares) | 234 | 301 | 447 |