Income taxes (Significant components of deferred tax assets and liabilities) (Details) - CAD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	$ (51,296,000)	$ (92,791,000)
Deferred tax assets	843,131,000	892,860,000
Deferred tax liabilities	0	0
Net deferred tax asset (liability)	843,131,000	892,860,000	$ 984,071,000
Property, plant and equipment [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	(41,454,000)	67,736,000
Net deferred tax assets	475,008,000	515,872,000
Provision for reclamation [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	(11,237,000)	(4,157,000)
Net deferred tax assets	188,422,000	199,659,000
Inventories [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	(4,979,000)	3,292,000
Net deferred tax assets	6,561,000	11,540,000
Net deferred tax liabilities	0	0
Foreign exploration and development [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	(398,000)	(51,000)
Net deferred tax assets	2,191,000	2,589,000
Income tax losses (gains) [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	(8,108,000)	(141,907,000)
Net deferred tax assets	85,668,000	93,776,000
Defined benefit plan actuarial losses [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	0	0
Net deferred tax assets	5,233,000	4,279,000
Long-term investments and other, deferred tax assets [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	14,880,000	(17,704,000)
Net deferred tax assets	80,048,000	65,145,000
Deferred tax assets [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	(51,296,000)	(92,791,000)
Net deferred tax assets	843,131,000	892,860,000
Property, plant and equipment [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	0	0
Net deferred tax liabilities	0	0
Inventories [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	0	0
Net deferred tax liabilities	0	0
Deferred tax liabilities [Member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Net deferred tax asset, recognized in earnings	0	0
Net deferred tax liabilities	$ 0	$ 0

The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2024-01-01
-Paragraph 81
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-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 54
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2024-01-01
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_56&doctype=Standard
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- Definition

The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2024-01-01
-Paragraph 81
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No definition available.

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The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2024-01-01
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The amount of deferred tax liabilities net of deferred tax assets, when the absolute amount of deferred tax liabilities is greater than the absolute amount of deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

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