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Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2015

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,		2015				2014				2013
Share option plan (note 22(b))		$	716			$	921			$	981
Liability classified restricted share unit plan (note 22(d(i)))		(80		)		790				2,652
Equity classified restricted share unit plan (note 22(d(ii)))		713				419				—
Equity performance restricted share unit plan (note 22(e))		431				94				—
Liability classified deferred stock unit plan (note 22(f(i)))		(735		)		(1,100		)		2,560
Equity classified deferred stock unit plan (note 22(f(ii)))		651				2,181				—
		$	1,696			$	3,305			$	6,193

Schedule of stock options activity

		Number of options			Weighted average exercise price $ per share
Outstanding at December 31, 2012		3,029,734			5.70
Granted		177,400			5.91
Exercised(i)		(295,230	)		3.98
Forfeited		(698,624	)		7.12
Outstanding at December 31, 2013		2,213,280			5.51
Exercised(i)		(385,880	)		3.49
Forfeited		(61,480	)		7.83
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

(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, 2015:

		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		288,900			6.4 years		$	2.75			149,420			6.5 years		$	2.75
$2.79		450,000			6.5 years		$	2.79			150,000			6.5 years		$	2.79
$3.69		29,100			2.9 years		$	3.69			29,100			2.9 years		$	3.69
$4.90		40,000			6.3 years		$	4.90			24,000			6.3 years		$	4.90
$5.00		127,760			0.4 years		$	5.00			127,760			0.4 years		$	5.00
$5.91		149,200			8.0 years		$	5.91			59,680			8.0 years		$	5.91
$6.56		79,860			5.9 years		$	6.56			63,080			5.9 years		$	6.56
$8.28		10,000			3.5 years		$	8.28			10,000			3.5 years		$	8.28
$8.58		30,000			4.7 years		$	8.58			30,000			4.7 years		$	8.58
$9.33		59,780			4.1 years		$	9.33			59,780			4.1 years		$	9.33
$10.13		59,060			5.0 years		$	10.13			59,060			5.0 years		$	10.13
$13.50		74,340			1.9 years		$	13.50			74,340			1.9 years		$	13.50
$16.46		50,000			2.3 years		$	16.46			50,000			2.3 years		$	16.46
		1,448,000			5.4 years		$	5.33			886,220			4.6 years		$	6.52

Schedule of performance restricted share units

		Number of units
Outstanding at December 31, 2013		—
Granted		65,636
Dividend equivalents granted		536
Outstanding at December 31, 2014		66,172
Granted		350,724
Dividend equivalents granted		6,696
Outstanding at December 31, 2015		423,592

Schedule of stock plan activity

Liability classified deferred stock unit plan

		Number of units
Outstanding at December 31, 2012		625,156
Issued		141,509
Redeemed		(179,831	)
Outstanding at December 31, 2013		586,834
Issued		7,674
Redeemed		(63,886	)
Outstanding at December 31, 2014		530,622
Issued		—
Modified		571,569
Redeemed		(173,317	)
Outstanding at December 31, 2015		928,874

Senior executive stock option plan

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

Schedule of assumptions used to value stock option grants

The weighted average assumptions used in estimating the fair value of the fully vested senior executive stock options as at December 31, 2015 and 2014 are as follows:

Year ended December 31,		2015			2014			2013
Number of senior executive stock options		—			258,200			550,000
Weighted average fair value per option granted ($)		—			0.08			1.71
Weighted average assumptions:
Dividend yield		—	%		2.20	%		N/A
Expected volatility		—	%		49.68	%		39.12	%
Risk-free interest rate		—	%		0.25	%		0.22	%
Expected life (years)		0.0			0.4			1.4

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, 2012		1,110,275
Granted		555,204
Vested		(154,330	)
Forfeited		(487,205	)
Outstanding at December 31, 2013		1,023,944
Dividend equivalents granted		695
Vested		(350,271	)
Forfeited		(58,865	)
Outstanding at December 31, 2014		615,503
Dividend equivalents granted		—
Vested		(277,707	)
Forfeited		(47,006	)
Outstanding at December 31, 2015		290,790

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, 2013		—			—
Granted		274,256			7.98
Dividend equivalents granted		11,557			6.15
Vested		(605	)		7.75
Forfeited		(22,300	)		7.87
Outstanding at December 31, 2014		262,908			7.91
Granted		557,650			3.01
Dividend equivalents granted		22,882			3.03
Modified		(156	)		3.62
Vested		(19,798	)		3.63
Forfeited		(49,330	)		6.37
Outstanding at December 31, 2015		774,156			4.45

Deferred share unit plan

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

Schedule of stock plan activity

Equity classified deferred stock unit plan

		Number of units			Weighted average exercise price $ per share
Outstanding at December 31, 2013		—			—
Granted		161,007			6.52
Dividend equivalents issued		8,721			6.10
Outstanding at December 31, 2014		169,728			6.50
Issued		378,867			3.29
Dividend equivalents granted		22,974			3.07
Modified		(571,569	)		2.58
Outstanding at December 31, 2015		—			—

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