Capital Stock and Stock-Based Awards - Schedule of Intrinsic value of stock options exercised, pretax stock-based compensation cost and related tax benefits (Details) - USD ($) $ / shares in Units, $ in Millions |
12 Months Ended | ||
|---|---|---|---|
May 31, 2026 |
May 31, 2025 |
May 31, 2024 |
|
| Share-Based Payment Arrangement [Abstract] | |||
| Total intrinsic value of stock options exercised | $ 8.0 | $ 0.5 | $ 6.4 |
| Total stock-based compensation cost (pretax) | 8.5 | 9.3 | 11.0 |
| Tax benefits (shortfalls) related to stock-based compensation cost | $ 0.6 | $ (2.5) | $ 5.0 |
| Weighted average grant date fair value per option (in Dollars per share) | $ 6.91 | $ 11.92 | $ 11.53 |