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Share-Based Payment Plans - Stock Options (Details) shares in Millions | 12 Months Ended
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Dec. 31, 2019 CAD ($) shares
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |
Number of options (in shares) | shares | 3.8
Weighted average remaining contractual life (in years) | 4 years 2 months 12 days
Weighted average exercise price (in dollars per share) | $ 8.41
Minimum |
Disclosure of range of exercise prices of outstanding share options [line items] |
Exercise price of outstanding share options (in dollars per share) | 5.00
Maximum |
Disclosure of range of exercise prices of outstanding share options [line items] |
Exercise price of outstanding share options (in dollars per share) | $ 30.00
5.00 - 9.00 |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |
Number of options (in shares) | shares | 3.3
Weighted average remaining contractual life (in years) | 4 years 8 months 12 days
Weighted average exercise price (in dollars per share) | $ 6.34
5.00 - 9.00 | Minimum |
Disclosure of range of exercise prices of outstanding share options [line items] |
Exercise price of outstanding share options (in dollars per share) | 5.00
5.00 - 9.00 | Maximum |
Disclosure of range of exercise prices of outstanding share options [line items] |
Exercise price of outstanding share options (in dollars per share) | $ 9.00
22.00 - 30.00 |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |
Number of options (in shares) | shares | 0.5
Weighted average remaining contractual life (in years) | 1 month 6 days
Weighted average exercise price (in dollars per share) | $ 23.44
22.00 - 30.00 | Minimum |
Disclosure of range of exercise prices of outstanding share options [line items] |
Exercise price of outstanding share options (in dollars per share) | 22.00
22.00 - 30.00 | Maximum |
Disclosure of range of exercise prices of outstanding share options [line items] |
Exercise price of outstanding share options (in dollars per share) | $ 30.00

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