Other long-term obligations - Table Narrative (Detail) - CAD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Other Liabilities Disclosure [Abstract]
Employee retirement benefit obligations in current liabilities	$ 62	$ 62
Asset retirement obligations and other environmental liabilities in current liabilities	235	235
Lease liability due within one year, Operating leases	77	87
Undiscounted commitments	$ 56	$ 54

Asset retirement obligation and other environmental liabilities current.

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- Definition

Lessor, Operating Lease, Lease Not yet Commenced, Undiscounted Commitments

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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