Supplemental Information - Employee Compensation Costs (Details) - CAD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Employee Compensation [Line Items]
Employee compensation costs	$ 31,867	$ 46,646
Operating
Disclosure Of Employee Compensation [Line Items]
Employee compensation costs	9,065	12,918
General and administrative
Disclosure Of Employee Compensation [Line Items]
Employee compensation costs	$ 22,802	$ 33,728

The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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