ENVIRONMENTAL LIABILITIES - Summary of Estimated Future Environmental Expenditures (Details) $ in Millions	Dec. 31, 2025 CAD ($)
Environmental Remediation Obligations [Abstract]
2026	$ 7
2027	6
2028	2
2029	1
2030	2
Thereafter	26
Total	$ 44

Estimated future environmental expenditures due.

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Estimated future environmental expenditures due in five year.

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Estimated future environmental expenditures due in four year.

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Estimated future environmental expenditures due in one year.

No definition available.

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Estimated future environmental expenditures due in three year.

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Estimated future environmental expenditures due in two year.

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Estimated future environmental expenditures due thereafter.

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