Amount of cash inflow from exercise of option under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Number of share options (or share units) exercised during the current period.

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Stock-based compensation - Share options plan (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 $ / shares shares	Dec. 31, 2019 CAD ($) shares	Dec. 31, 2018 $ / shares	Dec. 31, 2018 CAD ($) shares
Number of options
Exercised (in shares))		(327,000)		(297,940)
Weighted average exercise price $ per share
Proceeds from options exercised \| $		$ 1,953		$ 1,023
Share option plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)	2,495,619	2,495,619
Number of options
Beginning balance (in shares)		565,600		913,540
Exercised (in shares))		(327,000)		(297,940)
Forfeited or expired (in shares)				(50,000)
Ending balance (in shares)		238,600		565,600
Weighted average exercise price $ per share
Beginning balance (CAD per share) \| $ / shares			$ 5.36
Exercised (CAD per share) \| $ / shares	$ 5.97		3.43
Forfeited or expired (CAD per share) \| $ / shares			$ 16.46
Ending balance (CAD per share) \| $ / shares	$ 4.61
Proceeds from options exercised \| $		$ 1,953		$ 1,023
Total intrinsic value of options exercised \| $		$ 3,274		$ 1,351