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Share-Based Payment Plans - Stock Options (Details) shares in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 CAD shares | Dec. 31, 2016 CAD
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |
Number of options (in shares) | shares | 2.9 |
Weighted average remaining contractual life (in years) | 4 years |
Weighted average exercise price (in dollars per share) | CAD 14.26 |
Minimum |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |
Exercise price of outstanding share options (in dollars per share) |  | CAD 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) |  | 48.00
5.00 - 8.00 |  |
Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] |  |
Number of options (in shares) | shares | 1.9 |
Weighted average remaining contractual life (in years) | 5 years 7 months 6 days |
Weighted average exercise price (in dollars per share) | CAD 6.46 |
5.00 - 8.00 | 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 - 8.00 | Maximum |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |
Exercise price of outstanding share options (in dollars per share) |  | 6.00
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) | 2 years 1 month 6 days |
Weighted average exercise price (in dollars per share) | CAD 23.60 |
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
31.00 - 48.00 |  |
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) | CAD 34.35 |
31.00 - 48.00 | Minimum |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |
Exercise price of outstanding share options (in dollars per share) |  | 31.00
31.00 - 48.00 | Maximum |  |
Disclosure of range of exercise prices of outstanding share options [line items] |  |
Exercise price of outstanding share options (in dollars per share) |  | CAD 48.00

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