Share capital - Stock options plans and changes (Details)	6 Months Ended
	May 31, 2024 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Balance - end of period, number of options	14,316,900
Balance - end of period, weighted average exercise price | $ / shares	$ 1.78
Stock option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Balance - beginning of the year, number of options	12,649,400
Balance - beginning of the year, weighted average exercise price | $ / shares	$ 2.15
Number of options, Granted	2,775,000
Weighted average exercise price, Granted | $ / shares	$ 0.59
Number of options, Exercised	0
Number of options, Expired	(1,107,500)
Weighted average exercise price, Expired | $ / shares	$ 2.96
Balance - end of period, number of options	14,316,900
Balance - end of period, weighted average exercise price | $ / shares	$ 1.78