Stock-based compensation - expense (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2024 |
Jun. 30, 2023 |
Jun. 30, 2024 |
Jun. 30, 2023 |
|
| Other information about options outstanding | ||||
| Expense | $ 11.1 | $ 9.2 | $ 23.8 | $ 21.9 |
| Equity Award | ||||
| Other information about options outstanding | ||||
| Expense | 11.6 | 9.3 | 24.0 | 21.9 |
| Stock options | ||||
| Other information about options outstanding | ||||
| Expense | 2.6 | 3.6 | 5.7 | 7.2 |
| RSUs | ||||
| Other information about options outstanding | ||||
| Expense | 8.8 | 5.5 | 17.6 | 14.2 |
| Other | ||||
| Other information about options outstanding | ||||
| Expense | (0.3) | 0.1 | 0.5 | 0.5 |
| Liability Award | ||||
| Other information about options outstanding | ||||
| Expense | $ (0.5) | $ (0.1) | $ (0.2) | $ 0.0 |