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Common Shares (Tables) | 12 Months Ended
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Dec. 31, 2018
Common Shares |
Summary of outstanding warrants |
|  |  |  | Weighted |  | Weighted |  |  |  |
|  |  |  | average |  | average |  |  |  |
|  | Warrants |  | exercise price |  | remaining life |  |  |  |
|  | outstanding |  | per share |  | (yrs.) |  | Intrinsic value |
As of December 31, 2016 |  | 6,514,625 |  | $ | 1.92 |  | 2.6 |  | $ | — |
As of December 31, 2017 |  | 6,514,625 |  | $ | 1.92 |  | 1.6 |  | $ | — |
As of December 31, 2018 |  | 6,514,625 |  | $ | 1.92 |  | 0.6 |  | $ | — |
Summary of stock-based compensation expense |
|  |  |  | Year Ended December 31,
|  |  | 2018 |  | 2017 |  |
Stock options |  |  | $ | 320 |  | $ | 36 |  |
Restricted stock units |  |  |  | 662 |  |  | 838 |  |
|  |  | $ | 982 |  | $ | 874 |  |
Phantom units |  |  |  | 23 |  |  | — |  |
Summary of option activity |
|  |  |  | Weighted average |  | Weighted average |  | Aggregate |
|  | Number of |  | exercise price |  | remaining |  | intrinsic |
|  | options |  | per option |  | contractual term |  | value |
Outstanding - December 31, 2016 |  | 1,544,500 |  |  | 1.05 |  | 1.79 |  | $ | 626 |
Expired |  | (400,000) |  |  | 2.87 |  |  |  |  | — |
Outstanding - December 31, 2017 |  | 1,144,500 |  | $ | 0.42 |  | 1.15 |  | $ | 346 |
Granted |  | 1,142,000 |  |  | 0.71 |  |  |  |  |  |
Exercised |  | (218,600) |  |  | 0.39 |  |  |  |  | 36 |
Cancelled/Forfeited |  | (748,751) |  |  | 0.36 |  |  |  |  |  |
Outstanding - December 31, 2018 |  | 1,319,149 |  | $ | 0.71 |  | 3.84 |  | $ | 1 |
Exercisable - December 31, 2018 |  | 559,480 |  | $ | 0.70 |  | 3.23 |  | $ | 1 |
Summary of the status of unvested stock options |
|  |  |  |  |  |  | Weighted |
|  |  |  | Weighted |  | average |
|  |  |  | average |  | remaining |
|  |  |  | grant-date |  | amortization |
|  | Number of |  | fair value |  | period |
|  | options |  | per option |  | (Years) |
Unvested - December 31, 2016 |  | 296,250 |  |  | 0.49 |  | 1.23 |
Vested |  | (50,000) |  |  | 0.69 |  |  |
Unvested - December 31, 2017 |  | 246,250 |  | $ | 0.22 |  | 0.99 |
Granted |  | 1,142,000 |  |  | 0.45 |  |  |
Cancelled/Forfeited |  | (246,250) |  |  | 0.22 |  |  |
Vested |  | (382,331) |  |  | 0.45 |  |  |
Unvested - December 31, 2018 |  | 759,669 |  | $ | 0.45 |  | 1.14 |
Summary of stock option assumptions |
|  | 2018 |  |
Expected volatility |  | 76.2 | % |
Risk-free interest rate |  | 2.7 | % |
Expected life (years) |  | 5 |  |
Dividend yield |  | 0 | % |
Forfeiture assumption |  | — | % |
Summary of restricted stock unit activity |
|  |  |  | Weighted average |
|  | Number |  | grant-date fair |
|  | of RSUs |  | value per RSU |
Unvested - December 31, 2016 |  | 2,668,387 |  | $ | 0.49 |
Cancelled/forfeited |  | (441,084) |  |  | 0.34 |
Vested, net of shares withheld |  | (1,625,399) |  |  | 0.38 |
Granted |  | 966,003 |  |  | 0.82 |
Unvested - December 31, 2017 |  | 1,567,907 |  | $ | 0.85 |
Cancelled/forfeited |  | (246,683) |  |  | 0.90 |
Vested, net of shares withheld |  | (637,554) |  |  | 0.88 |
Granted |  | 319,000 |  |  | 0.75 |
Unvested - December 31, 2018 |  | 1,002,670 |  | $ | 0.78 |
Summary of phantom units |
|  |  |  | Weighted average |
|  | Number of |  | remaining |
|  | phantom units |  | contractual term |
Unvested - December 31, 2017 |  | — |  |  |
Granted |  | 265,000 |  |  |
Unvested - December 31, 2018 |  | 265,000 |  | 1.50 |
Schedule of weighted average common shares |
|  | At December 31, |
|  | 2018 |  | 2017 |
Basic common shares |  | 99,738,461 |  | 98,627,255 |
Effect of dilutive stock-based awards |  | — |  | — |
Diluted common shares |  | 99,738,461 |  | 98,627,255 |

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