Major commitments and contingencies (Environmental Matters) (Details) - CAD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Accrual for Environmental Loss Contingencies [Roll Forward] | |||
| Beginning of year | $ 56 | $ 58 | $ 59 |
| Accruals and other | 38 | 15 | 17 |
| Payments | (29) | (19) | (19) |
| Foreign exchange | (1) | 2 | 1 |
| End of year | 64 | 56 | 58 |
| Current portion - End of year | $ 38 | 40 | 39 |
| Anticipated environmental liability disbursement time frame (in years) | 5 years | ||
| Regulatory Compliance [Abstract] | |||
| Environmental operating expenses | $ 48 | 47 | 32 |
| Environmental capital expenditures | $ 25 | $ 27 | $ 13 |
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- Definition May incur significant capital and operating costs associated with environmental regulatory compliance and clean-up requirements in its railroad operations and relating to its past and present ownership, operation and control of real property. No definition available.
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- Definition Site Contingency, Time Frame Of Disbursements, Term No definition available.
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of foreign currency translation gain (loss) which decreases (increases) the accrual for environmental loss contingencies. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash outflow to settle environmental loss contingencies. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of environmental remediation costs capitalized. These expenditures may relate to long-lived improvements in operating facilities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before recovery, of expense for known and estimated future costs arising from requirement to perform environmental remediation. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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