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Stock-based compensation (Tables) | 12 Months Ended
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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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- Definition Tabular disclosure of share-based compensation plans that may be presented in a single table for outstanding, vested and expected to vest, and exercisable awards. The information that may be disclosed in this table may include, but is not limited to, number of shares, weighted average exercise price, weighted average remaining contractual life, and aggregate intrinsic value. + References No definition available. + Details
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