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The exercise price of outstanding share options.

+ References

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- Definition

The number of share options outstanding in a share-based payment arrangement.

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- Definition

The number of share options exercisable in a share-based payment arrangement.

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- Definition

The weighted average exercise price of share options exercisable in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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- Definition

The weighted average remaining contractual life of outstanding share options. [Refer: Weighted average [member]]

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Disclosure of number and weighted average remaining contractual life of exercisable share options

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No definition available.

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Weighted average remaining contractual life of exercisable share options.

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No definition available.

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Share Capital - Options Held by Officers and Employees (Details)	12 Months Ended
	Dec. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares	Dec. 31, 2018 $ / shares
Options Outstanding
Outstanding	2,123,800	4,051,080	4,987,542
Weighted Average Exercise Price per Share (in cad per share)	$ 32.45	$ 32.17	$ 31.11
Officers and employees
Options Outstanding
Outstanding	2,123,800
Weighted Average Remaining Contractual Life in Years	1 year 5 months 12 days
Weighted Average Exercise Price per Share (in cad per share)	$ 32.45
Options Exercisable
Shares Exercisable #	1,816,592
Weighted Average Remaining Contractual Life in Years	1 year 3 months 18 days
Weighted Average Exercise Price per Share (in cad per share)	$ 32.36
Bottom of range
Options Outstanding
Range of Exercise Prices per Share (in cad per share)	31.75
Top of range
Options Outstanding
Range of Exercise Prices per Share (in cad per share)	$ 32.98