Share capital - Narrative (Details) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	May 31, 2021 USD ($) $ / shares shares	Feb. 28, 2021 USD ($)	May 31, 2020 USD ($)	Feb. 29, 2020 USD ($)	May 31, 2021 USD ($) $ / shares shares	May 31, 2021 USD ($) $ / shares $ / shares shares	May 31, 2020 USD ($) $ / shares shares	May 31, 2020 USD ($) $ / shares	May 31, 2021 $ / shares	Nov. 30, 2020 shares	Nov. 30, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, conversion					1
Common stock committed for issuance	144,446,485				144,446,485	144,446,485				144,137,850
Stock-based compensation | $	$ (524)	$ (2,148)	$ (770)	$ (1,196)
Non-vested stock options outstanding	11,123,316				11,123,316	11,123,316
Weighted average exercise price options outstanding | $ / shares	$ 2.03				$ 2.03	$ 2.03
Aggregate intrinsic value, vested options | $	$ 6,800		$ 8,300		$ 6,800	$ 6,800	$ 8,300	$ 8,300
Aggregate intrinsic value, options exercised | $					$ 710		180
Share capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock committed for issuance	144,446,485				144,446,485	144,446,485				144,137,850	140,427,761
Nonvested Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested stock options outstanding	3,176,337				3,176,337	3,176,337
Weighted average exercise price options outstanding | $ / shares									$ 2.63
Stock option expense not yet recognized | $	$ 1,170				$ 1,170	$ 1,170
Period for recognition of stock compensation expense					2 years
DSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 70		$ 390
Granted units					35,406
Outstanding grants	1,253,926				1,253,926	1,253,926				1,218,520
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding grants	0				0	0
Employees, consultants and directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, expiration period					5 years
Stock options granted					3,374,150		2,325,000
Vesting period							2 years
Weighted-average exercise price | $ / shares						$ 2.52		$ 2.93
Stock options granted, weighted average fair value | $ / shares					$ 0.84		$ 0.96
Directors, employees and service providers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 2,600		$ 1,580