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Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2020

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of stock-based compensation expenses included in general and administrative expenses

Stock-based compensation expenses included in general and administrative expenses are as follows:

Year ended December 31,			Note						2020						2019
Restricted share unit plan			17(a)						$	1,991					$	1,933
Performance restricted share unit plan			17(b)						2,031						1,892
Deferred stock unit plan			17(c)						(2,078)						5,618
									$	1,944					$	9,443

Schedule of performance restricted share units

						Number of units						Weighted-average exercise price $ per share
Outstanding at December 31, 2018						741,117						5.92
Granted						122,274						13.12
Vested						(372,924)						4.45
Forfeited						(8,560)						8.09
Outstanding at December 31, 2019						481,907						8.85
Granted						211,754						8.55
Vested						(201,104)						8.51
Outstanding at December 31, 2020						492,557						8.86

Schedule of assumptions used in estimate of fair value

The Company estimated the fair value of the PSUs granted during the years ended December 31, 2020 and 2019 using a Monte Carlo simulation with the following assumptions:

						2020						2019
Risk-free interest rate						0.30		%				1.43		%
Expected volatility						48.71		%				40.12		%

Schedule of stock plan activity

						Number of units
Outstanding at December 31, 2018						1,126,239
Granted						82,191
Redeemed						(307,385)
Outstanding at December 31, 2019						901,045
Granted						114,020
Redeemed						(9,562)
Outstanding at December 31, 2020						1,005,503

Schedule of stock options activity

						Number of options						Weighted-average exercise price $ per share
Outstanding at December 31, 2018						565,600						5.40
Exercised(i)						(327,000)						5.97
Outstanding at December 31, 2019						238,600						4.61
Exercised(i)						(109,100)						4.91
Forfeited or expired						(4,500)						10.13
Outstanding at December 31, 2020						125,000						4.16

(i) All stock options exercised resulted in new common shares being issued (note 15(a)).

Summary of information about stock options outstanding

The following table summarizes information about stock options outstanding at December 31, 2020:

						Options outstanding and exercisable
Exercise price						Number						Weighted-average remaining life						Weighted- average exercise price
$2.75						73,400						1.7 years						$	2.75
$5.91						31,100						3.0 years						$	5.91
$6.56						20,500						0.9 years						$	6.56
						125,000						1.9 years						$	4.16

Equity classified restricted share unit plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of restricted share unit plan activity

						Number of units						Weighted-average exercise price $ per share
Outstanding at December 31, 2018						948,093						5.88
Granted						193,450						13.40
Vested						(465,194)						4.15
Forfeited						(26,272)						6.01
Outstanding at December 31, 2019						650,077						9.35
Granted						298,142						8.55
Vested						(269,484)						6.19
Forfeited						(37,264)						8.81
Outstanding at December 31, 2020						641,471						10.34

X

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