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Share Capital (Schedule of Stock Options Range for Outstanding and Exercisable Shares) (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 shares $ / shares | Dec. 31, 2019 shares $ / shares | Dec. 31, 2018 shares $ / shares
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 3,476,579 | 4,465,262 | 6,655,455
Outstanding weighted average exercise price (CAD per share) | $ 6.80 | $ 6.59 | $ 7.38
Weighted average remaining contractual life of options outstanding (years) | 4 years 4 months 20 days |  |
Number of options exercisable (in shares) | shares | 1,722,702 |  |
Exercisable weighted average exercise price (CAD per share)) | $ 6.51 |  |
$3.01 - $5.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 560,000 |  |
Outstanding weighted average exercise price (CAD per share) | $ 3.75 |  |
Weighted average remaining contractual life of options outstanding (years) | 2 years 18 days |  |
Number of options exercisable (in shares) | shares | 560,000 |  |
Exercisable weighted average exercise price (CAD per share)) | $ 3.75 |  |
$6.01 - $7.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 1,596,265 |  |
Outstanding weighted average exercise price (CAD per share) | $ 6.57 |  |
Weighted average remaining contractual life of options outstanding (years) | 4 years 8 months 15 days |  |
Number of options exercisable (in shares) | shares | 679,852 |  |
Exercisable weighted average exercise price (CAD per share)) | $ 6.57 |  |
$7.01 - $8.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 809,184 |  |
Outstanding weighted average exercise price (CAD per share) | $ 7.62 |  |
Weighted average remaining contractual life of options outstanding (years) | 6 years 7 days |  |
Number of options exercisable (in shares) | shares | 291 |  |
Exercisable weighted average exercise price (CAD per share)) | $ 7.07 |  |
$8.01 - $9.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 28,571 |  |
Outstanding weighted average exercise price (CAD per share) | $ 8.63 |  |
Weighted average remaining contractual life of options outstanding (years) | 6 years 1 month 28 days |  |
Number of options exercisable (in shares) | shares | 0 |  |
Exercisable weighted average exercise price (CAD per share)) | $ 0 |  |
$9.01 - $10.00 |  |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |  |
Number of options outstanding (in shares) | shares | 482,559 |  |
Outstanding weighted average exercise price (CAD per share) | $ 9.62 |  |
Weighted average remaining contractual life of options outstanding (years) | 3 years 2 months 4 days |  |
Number of options exercisable (in shares) | shares | 482,559 |  |
Exercisable weighted average exercise price (CAD per share)) | $ 9.62 |  |
Bottom of range [member] | $3.01 - $5.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 3.01 |  |
Bottom of range [member] | $6.01 - $7.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 7.01 |  |
Bottom of range [member] | $7.01 - $8.00 |  |  |
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 - $5.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 7.00 |  |
Top of range [member] | $6.01 - $7.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | 11.00 |  |
Top of range [member] | $7.01 - $8.00 |  |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |  |
Exercise price of outstanding share options | $ 19.00 |  |

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