Derivative and hedging activities - effect of net investment hedges on AOCI and the statement of operations (Details) - Net investment hedges - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Derivative [Line Items] | ||
| Amount of gain or (loss) recognized in OCI on Derivative | $ (89.9) | $ 60.9 |
| Amount of gain or (loss) recognized in income on Derivative (amount excluded from effectiveness testing) | 9.2 | 12.7 |
| Cross-currency swaps | ||
| Derivative [Line Items] | ||
| Amount of gain or (loss) recognized in OCI on Derivative | (89.9) | 60.9 |
| Cross-currency swaps | Interest expense, net | ||
| Derivative [Line Items] | ||
| Amount of gain or (loss) recognized in income on Derivative (amount excluded from effectiveness testing) | $ 9.2 | $ 12.7 |