Decommissioning Liabilities - Summary of Decommissioning Provision (Detail) $ in Millions	9 Months Ended
Sep. 30, 2024 CAD ($)
Provision for decommissioning, restoration and rehabilitation costs [abstract]
Beginning balance	$ 4,155
Liabilities Incurred	17
Liabilities Settled	(170)
Liabilities disposed	(72)
Unwinding of Discount on Decommissioning Liabilities (Note 4)	169
Exchange Rate Movements	10
Ending balance	$ 4,109

The increase (decrease) in other provisions resulting from foreign currency exchange rate changes on provisions measured in a currency different from the entity's presentation currency. [Refer: Other provisions]

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The increase (decrease) in other provisions resulting from transfers and changes that the entity does not separately disclose in the same statement or note. [Refer: Other provisions]

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The amount recognised for new other provisions. [Refer: Other provisions]

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The amount of provision for costs related to decommissioning, restoration and rehabilitation. [Refer: Other provisions]

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The amount used (ie incurred and charged against the provision) for other provisions. [Refer: Other provisions]

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