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Share Capital (Schedule of Stock Options Range for Outstanding and Exercisable Shares) (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 shares $ / shares | Dec. 31, 2018 shares $ / shares | Dec. 31, 2017 shares $ / shares
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | $ 9.66 | $ 5.89 |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 4,465,262 | 6,655,455 | 10,429,345
Weighted average exercise price of share options outstanding in share-based payment arrangement | $ 6.59 | $ 7.38 | $ 7.94
Weighted average remaining contractual life of outstanding share options | 3 years 9 months 26 days |  |
Number of options exercisable (in shares) | shares | 2,633,830 |  |
Weighted average exercise price of share options exercisable in share-based payment arrangement | $ 6.38 |  |
$3.01 - $7.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 3,069,246 |  |
Weighted average exercise price of share options outstanding in share-based payment arrangement | $ 5.57 |  |
Weighted average remaining contractual life of outstanding share options | 4 years 8 months 12 days |  |
Number of options exercisable (in shares) | shares | 1,446,515 |  |
Weighted average exercise price of share options exercisable in share-based payment arrangement | $ 4.44 |  |
$7.01 - $11.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 1,295,096 |  |
Weighted average exercise price of share options outstanding in share-based payment arrangement | $ 8.32 |  |
Weighted average remaining contractual life of outstanding share options | 2 years 15 days |  |
Number of options exercisable (in shares) | shares | 1,086,395 |  |
Weighted average exercise price of share options exercisable in share-based payment arrangement | $ 8.11 |  |
$11.01 - $15.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 100,920 |  |
Weighted average exercise price of share options outstanding in share-based payment arrangement | $ 15.47 |  |
Weighted average remaining contractual life of outstanding share options | 22 days |  |
Number of options exercisable (in shares) | shares | 100,920 |  |
Weighted average exercise price of share options exercisable in share-based payment arrangement | $ 15.47 |  |
Bottom of range [member] | $3.01 - $7.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 3.01 |  |
Bottom of range [member] | $7.01 - $11.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 7.01 |  |
Bottom of range [member] | $11.01 - $15.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 11.01 |  |
Top of range [member] | $3.01 - $7.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 7.00 |  |
Top of range [member] | $7.01 - $11.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 11.00 |  |
Top of range [member] | $11.01 - $15.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | $ 19.00 |  |

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