Stock-based compensation (Schedule of stock option activity) (Details) - CAD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of options, Outstanding, beginning of year	1,185,000
Number of options, Outstanding, end of year	1,185,000	1,185,000
Number of options, Exercisable, end of year	927,500
Number of options, Unvested	257,500
Weighted- average exercise price beginning of year	$ 2.06
Weighted-average exercise price end of year	2.06	$ 2.06
Stock options Exercisable, Weighted-average exercise price end of year	1.46
Stock options Unvested, Weighted average exercise price	$ 3.68
Stock options, Outstanding, Weighted average remaining contractual life (years)	3 years 11 months 8 days	4 years 2 months 4 days
Stock options, Exercisable, Weighted average remaining contractual life (years)	3 years 7 months 2 days
Unvested, Weighted average remaining contractual life (years)	4 years 8 months 8 days
Stock options, Outstanding, Aggregate intrinsic value	$ 1.66	$ 1.89
Stock options, Exercisable, Aggregate intrinsic value	2.26
Stock options, Unvested, Aggregate intrinsic value	$ 0.04

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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