Pension and other post-retirement benefits (Percentages of the total fair value of assets) (Details) - Pension Plans [member] - CAD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Disclosure of fair value of plan [line items]
The percentages of the total fair value of assets	100.00%	100.00%
Description of the refundable tax account held by CRA	equal to half of the sum of the realized investment income plus employer contributions less half of the benefits paid by the plan
Related Parties [member]
Disclosure of fair value of plan [line items]
Defined benefit plan assets	$ 0	$ 0
Canadian Equity Securities [member]
Disclosure of fair value of plan [line items]
The percentages of the total fair value of assets	7.00%	6.00%
US Equity Securities [Member]
Disclosure of fair value of plan [line items]
The percentages of the total fair value of assets	12.00%	11.00%
Global Equity Securities [member]
Disclosure of fair value of plan [line items]
The percentages of the total fair value of assets	6.00%	6.00%
Canadian Fixed Income [member]
Disclosure of fair value of plan [line items]
The percentages of the total fair value of assets	31.00%	28.00%
Other [member]
Disclosure of fair value of plan [line items]
The percentages of the total fair value of assets	44.00%	49.00%

The description of the refundable tax account held by Canada Revenue Agency.

No definition available.

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- Definition

Percentage of the total fair value of assets in the pension plans for each asset category.

+ References

No definition available.

+ Details

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2023-01-01
-Paragraph 140
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_140_a&doctype=Standard
-URIDate 2023-03-23

+ Details

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