Debt (Schedule of US dollar-Denominated Debt) (Details) - US Dollar-Denominated $ in Millions, $ in Millions |
Dec. 31, 2025
CAD ($)
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Dec. 31, 2025
USD ($)
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Dec. 31, 2024
CAD ($)
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Dec. 31, 2024
USD ($)
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| Debt Instrument [Line Items] | ||||
| Debt outstanding | $ 13,610 | $ 9,917 | $ 13,898 | $ 9,662 |
| Notes and Debentures | ||||
| Debt Instrument [Line Items] | ||||
| Debt outstanding | 9,350 | 8,650 | ||
| Commercial paper | ||||
| Debt Instrument [Line Items] | ||||
| Debt outstanding | 90 | 501 | ||
| Finance lease liabilities | ||||
| Debt Instrument [Line Items] | ||||
| Debt outstanding | 4 | 5 | ||
| Equipment loans and other | ||||
| Debt Instrument [Line Items] | ||||
| Debt outstanding | $ 473 | $ 506 |
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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