Share capital - Authorized unlimited common shares, no par value (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Nov. 30, 2023	Nov. 30, 2022	Nov. 30, 2021
Class of Stock [Line Items]
Unlimited common shares authorized	Unlimited	Unlimited
Common Stock, No Par Value	$ 0	$ 0
Private Placement, net of share issue cost, Ascribed value	$ 3,115
Services settled by common shares, Ascribed value	$ 99	$ 114
Number of shares, issued	155,925,990	146,225,035
Share capital
Class of Stock [Line Items]
Exercise of options, Number of shares		81,674	871,961
Private Placement, net of share issue cost, Number of shares	5,854,545
Private Placement, net of share issue cost, Ascribed value	$ 3,115
Restricted share units, Number of shares	3,091,614	992,081
Restricted share units, Ascribed value	$ 1,911
Deferred share units, Number of shares	415,056
Deferred share units, Ascribed value	$ 468
NovaGold deferred share units conversion, Number of shares	1,130
NovaGold deferred share units conversion, Ascribed value	$ 4
Services settled by common shares, Number of shares	195,105	110,000
Services settled by common shares, Ascribed value	$ 99	$ 114
Joint venture equity contribution (note 3(b)), Number of shares	143,505	51,000
Joint venture equity contribution (note 3(b)), Ascribed value	$ 111
Ending balance, Number of shares outstanding	155,925,990	146,225,035
Beginning balance, Number of shares	146,225,035
Contributed surplus.
Class of Stock [Line Items]
NovaGold deferred share units conversion, Ascribed value	$ (4)