Share-Based Compensation (Share-Based Compensation Expense) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Share based compensation expense | $ 26.0 | $ 24.1 | $ 48.0 | $ 44.2 |
| Tax benefit | (6.3) | (5.8) | (11.6) | (10.7) |
| After-tax expense | (19.7) | (18.3) | (36.4) | (33.5) |
| Stock Options [Member] | ||||
| Share based compensation expense | 5.4 | 4.8 | 10.7 | 8.9 |
| Restricted Stock Units (RSUs) [Member] | ||||
| Share based compensation expense | 8.7 | 8.8 | 15.0 | 14.6 |
| Phantom Share Units (PSUs) [Member] | ||||
| Share based compensation expense | 10.8 | 9.6 | 21.1 | 19.1 |
| Deferred Compensation [Member] | ||||
| Share based compensation expense | $ 1.1 | $ 0.9 | $ 1.2 | $ 1.6 |