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Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2016

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,		2016				2015
Share option plan (note 21(b))		$	587			$	716
Liability classified restricted share unit plan (note 21(d(i)))		52				(80		)
Equity classified restricted share unit plan (note 21(d(ii)))		1,384				713
Equity performance restricted share unit plan (note 21(e))		820				431
Liability classified deferred stock unit plan (note 21(f(i)))		3,187				(735		)
Equity classified deferred stock unit plan (note 21(f(ii)))		—				651
		$	6,030			$	1,696

Schedule of stock options activity

		Number of options			Weighted average exercise price $ per share
Outstanding at December 31, 2014		1,765,920			5.87
Exercised(i)		(30,080	)		2.75
Forfeited		(287,840	)		8.91
Outstanding at December 31, 2015		1,448,000			5.33
Exercised(i)		(102,040	)		2.77
Forfeited		(169,880	)		5.31
Outstanding at December 31, 2016		1,176,080			5.56

(i) All stock options exercised resulted in new common shares being issued (note 17(a)).

Summary of information about stock options outstanding

The following table summarizes information about stock options outstanding at December 31, 2016:

		Options outstanding									Options exercisable
Exercise price		Number			Weighted average remaining life		Weighted average exercise price				Number			Weighted average remaining life		Weighted average exercise price
$2.75		226,540			5.4 years		$	2.75			161,960			5.3 years		$	2.75
$2.79		400,000			5.5 years		$	2.79			250,000			5.5 years		$	2.79
$3.69		25,800			1.9 years		$	3.69			25,800			1.9 years		$	3.69
$4.90		40,000			5.3 years		$	4.90			32,000			5.3 years		$	4.90
$5.91		137,500			7.0 years		$	5.91			82,500			7.0 years		$	5.91
$6.56		73,660			4.9 years		$	6.56			73,660			4.9 years		$	6.56
$8.28		10,000			2.5 years		$	8.28			10,000			2.5 years		$	8.28
$8.58		30,000			3.7 years		$	8.58			30,000			3.7 years		$	8.58
$9.33		55,780			3.1 years		$	9.33			55,780			3.1 years		$	9.33
$10.13		54,960			4.0 years		$	10.13			54,960			4.0 years		$	10.13
$13.50		71,840			0.9 years		$	13.50			71,840			0.9 years		$	13.50
$16.46		50,000			1.3 years		$	16.46			50,000			1.3 years		$	16.46
		1,176,080			4.8 years		$	5.56			898,500			4.5 years		$	6.21

Schedule of performance restricted share units

		Number of units			Weighted average exercise price $ per share
Outstanding at December 31, 2014		66,172			8.50
Granted		357,420			4.19
Outstanding at December 31, 2015		423,592			4.86
Granted		343,706			4.97
Forfeited		(27,998	)		4.52
Outstanding at December 31, 2016		739,300			4.84

Schedule of stock plan activity

Liability classified deferred stock unit plan

		Number of units
Outstanding at December 31, 2014		530,622
Modified		571,569
Redeemed		(173,317	)
Outstanding at December 31, 2015		928,874
Granted		171,980
Redeemed		(158,917	)
Outstanding at December 31, 2016		941,937

Liability classified restricted share unit plan

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

Schedule of restricted share unit plan activity

Liability classified restricted share unit plan

		Number of units
Outstanding at December 31, 2014		615,503
Vested		(277,707	)
Forfeited		(47,006	)
Outstanding at December 31, 2015		290,790
Vested		(290,790	)
Forfeited		—
Outstanding at December 31, 2016		—

Equity classified restricted share unit plan

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

Schedule of restricted share unit plan activity

Equity classified restricted share unit plan

		Number of units			Weighted average exercise price $ per share
Outstanding at December 31, 2014		262,908			7.91
Granted		580,532			2.89
Modified		(156	)		3.62
Vested		(19,798	)		3.63
Forfeited		(49,330	)		6.37
Outstanding at December 31, 2015		774,156			4.45
Granted		501,523			3.78
Vested		(87,580	)		3.51
Forfeited		(64,124	)		3.50
Outstanding at December 31, 2016		1,123,975			4.20

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