Derivative financial instruments - EDF energy contracts - changing assumptions on impact on valuations (Details) - EDF Energy Contracts [Member] - Income approach [member] - Level 3	12 Months Ended
Dec. 31, 2025 USD ($)
Energy Price [Member]
Disclosure of information about amounts that affected statement of comprehensive income as result of hedge accounting [line items]
Decrease in value - Energy contract	$ (68,102,000)
Increase in value - Energy contract	$ 75,477,000
Percentage decrease	10.00%
Percentage increase	10.00%
CO2 price [Member]
Disclosure of information about amounts that affected statement of comprehensive income as result of hedge accounting [line items]
Decrease in value - Energy contract	$ 24,356,000
Increase in value - Energy contract	$ (27,482,000)
Percentage decrease	10.00%
Percentage increase	10.00%
At fair value
Disclosure of information about amounts that affected statement of comprehensive income as result of hedge accounting [line items]
Hedging Financial Instruments	$ (39,239,000)

The amount of hedging financial instruments.

No definition available.

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- Definition

The amount of increase (decrease) in the fair value measurement of Derivative Financial Instrument due to a reasonably possible decrease in an unobservable input.

+ References

No definition available.

+ Details

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- Definition

The amount of increase (decrease) in the fair value measurement of Derivative Financial Instrument due to a reasonably possible increase in an unobservable input.

+ References

No definition available.

+ Details

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- Definition

The percentage of reasonable Possible decrease In Assumption.

+ References

No definition available.

+ Details

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- Definition

The percentage of reasonable Possible Increase In Assumption

+ References

No definition available.

+ Details

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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