Financial Risk Management - Credit Risk - Counterparties to derivative contracts (Details) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Financial Risk Management | ||
| Total derivative assets | $ 2,081.9 | $ 1,291.4 |
| Obligations that may be offset under net settlement arrangements | (99.8) | (38.2) |
| Fair value of collateral deposited for the benefit of the company | (1,931.3) | (1,063.4) |
| Excess collateral pledged by the company in favour of counterparties | 5.4 | 9.2 |
| Net derivative counterparty exposure after net settlement and collateral arrangements | 56.2 | 199.0 |
| Cash | ||
| Financial Risk Management | ||
| Financial assets pledged as collateral | 51.5 | 50.0 |
| Government securities | ||
| Financial Risk Management | ||
| Financial assets pledged as collateral | $ 1,919.2 | $ 1,015.1 |