Financial Instruments - Embedded Derivative Contract (Details) $ in Millions	Dec. 31, 2025 CAD ($) uSDPerMMBtu	Dec. 31, 2024 CAD ($)
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Fair value ($ millions) \| $	$ 57	$ 0
Bottom of range \| Natural gas embedded derivative
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Forward Prices \| uSDPerMMBtu	3.10
Top of range \| Natural gas embedded derivative
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Forward Prices \| uSDPerMMBtu	7.53
Level 3 \| Natural gas embedded derivative
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items]
Fair value ($ millions) \| $	$ 57
Discount Rate	4.60%

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- Definition

The discount rate used in the current estimate of the present value of the future cash flows expected to be derived from an asset or cash-generating unit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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

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- Definition

The amount of non-current derivative financial liabilities. [Refer: Derivative financial liabilities]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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