Share capital - Authorized unlimited common shares, no par value (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Nov. 30, 2022
Class of Stock [Line Items]
Unlimited common shares authorized	Unlimited		Unlimited
Common Stock, No Par Value	$ 0		$ 0
Beginning Balance	$ 145,428	$ 166,039	$ 166,039
Beginning balance, Number of shares issued	146,225,035
Services settled by common shares, Ascribed value	$ 4
Joint venture equity contribution (note 4(b)), Ascribed value	111
Ending Balance	$ 142,691	162,950	$ 145,428
Ending balance, Number of shares issued	148,722,699		146,225,035
Share capital
Class of Stock [Line Items]
Beginning balance, Number of shares	146,225,035
Beginning Balance	$ 182,178	$ 180,820	$ 180,820
Beginning balance, Ascribed value	$ 182,178
Exercise of options, Number of shares		31,674
Restricted share units, Number of shares	2,346,366	391,332
Restricted share units, Ascribed value	$ 1,538
Services settled by common shares, Number of shares	7,793
Services settled by common shares, Ascribed value	$ 4
Joint venture equity contribution (note 4(b)), Number of shares	143,505	31,469
Joint venture equity contribution (note 4(b)), Ascribed value	$ 111
Ending balance, Number of shares outstanding	148,722,699		146,225,035
Ending balance, Ascribed value	$ 183,831		$ 182,178
Ending Balance	$ 183,831	$ 181,571	$ 182,178