Stock-based compensation - expense (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|
| Other information about options outstanding | |||
| Expense | $ 46.4 | $ 46.8 | $ 40.5 |
| Stock options | |||
| Other information about options outstanding | |||
| Expense | 9.3 | 10.5 | 13.7 |
| RSUs | |||
| Other information about options outstanding | |||
| Expense | 37.1 | 35.0 | 25.5 |
| Other | |||
| Other information about options outstanding | |||
| Expense | 0.0 | 1.3 | 1.3 |
| Equity | |||
| Other information about options outstanding | |||
| Expense | 47.6 | 47.0 | 40.2 |
| Liability | |||
| Other information about options outstanding | |||
| Expense | $ (1.2) | $ (0.2) | $ 0.3 |