Other income (Details) - CAD ($) $ in Millions		12 Months Ended
Dec. 13, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Gain (loss) on foreign currency		$ 32	$ 12	$ 7
Other		8	10	(9)
Total other income		88	42	134
Proceeds from disposal of property		0	0	129
Land
Property, Plant and Equipment [Line Items]
Gain on disposal of land and property		48	20	7
Property
Property, Plant and Equipment [Line Items]
Gain on disposal of land and property	$ 129	$ 0	$ 0	$ 129
Proceeds from disposal of property	129
Nonoperating gain, after expense and tax	$ 112

Nonoperating Gains (Losses), After Tax

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- Definition

Other Nonoperating Income (Expense), Miscellaneous

+ References

No definition available.

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- Definition

Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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The aggregate amount of gains or losses resulting from nonoperating activities (for example, interest and dividend revenue, property, plant and equipment impairment loss, and so forth).

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of cash inflow for the sale of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

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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.

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