Share capital - Narrative (Details) $ / shares in Units, $ in Thousands	3 Months Ended						6 Months Ended
	May 31, 2024 USD ($) $ / shares shares	Feb. 29, 2024 USD ($) shares	Feb. 29, 2024 $ / shares	May 31, 2023 USD ($) shares	Feb. 28, 2023 USD ($) shares	Feb. 28, 2023 $ / shares	May 31, 2024 USD ($) $ / shares shares	May 31, 2024 USD ($) $ / shares $ / shares shares	May 31, 2023 USD ($)	May 31, 2024 $ / shares	Nov. 30, 2023 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares, conversion							1
Non-vested stock options outstanding	14,316,900						14,316,900	14,316,900
Private placement, net proceeds | $									$ 3,115
Stock-based compensation | $	$ (509)	$ (1,999)		$ (371)	$ (2,220)
Weighted average exercise price options outstanding | $ / shares	$ 1.78						$ 1.78	$ 1.78
Period for recognition of stock compensation expense							12 months
Common Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common stock committed for issuance	160,186,788						160,186,788	160,186,788			155,925,990
Shares issued for private placement, net of share issue cost (Shares)				5,854,545
Nonvested Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Non-vested stock options outstanding	2,533,339						2,533,339	2,533,339
Weighted average exercise price options outstanding | $ / shares										$ 0.66
Stock option expense not yet recognized | $	$ 300						$ 300	$ 300
DSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation | $							$ 1,600		1,800
Employee Stock Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Non-vested stock options outstanding	14,316,900						14,316,900	14,316,900			12,649,400
Weighted average exercise price options outstanding | $ / shares	$ 1.78						$ 1.78	$ 1.78			$ 2.15
Exercise of options, Number of shares							0
Stock options granted							2,775,000
Weighted-average exercise price | $ / shares							$ 0.59
Employees, consultants and directors
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock options granted, expiration period		5 years			5 years
Stock options granted	0	2,775,000		0	3,230,000
Vesting period							2 years
Weighted-average exercise price | $ / shares			$ 0.59			$ 0.78
Stock options granted, weighted average fair value | $ / shares			$ 0.27			$ 0.37		$ 0.27
Directors, employees and service providers
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation | $							$ 400		$ 600
Directors, employees and service providers | NovaGold Arrangement
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares, conversion							6
Directors, employees and service providers | NovaGold Arrangement | Nonvested Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Non-vested stock options outstanding	5,144						5,144	5,144
Common stock committed for issuance	859						859	859