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Share Capital (Stock Options) (Details) | 12 Months Ended
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Dec. 31, 2020 shares $ / shares | Dec. 31, 2019 shares $ / shares
Disclosure of share capital, reserves and other equity interest [Abstract] |  |
Number of options outstanding | shares | 4,465,262 | 6,655,455
Granted | shares | 876,425 | 965,876
Exercised | shares | (1,653,361) | (1,555,989)
Expired | shares | (211,747) | (1,600,080)
Number of options outstanding | shares | 3,476,579 | 4,465,262
Weighted average exercise price of share options outstanding (CAD$) | $ 6.59 | $ 7.38
Weighted average exercise price of share options granted (CAD$) | 7.66 | 6.59
Weighted average exercise price of share options exercised (CAD$) | 6.15 | 5.93
Weighted average exercise price of share options expired (CAD$) | 11.02 | 10.52
Weighted average exercise price of share options outstanding (CAD$) | 6.80 | 6.59
Weighted average share price for share options in share-based payment arrangement exercised during period at date of exercise | $ 10.90 | $ 9.66

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