Earnings Per Common Share (Details) - CAD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Earnings Per Common Share
Net earnings	$ 3,293	$ 4,458
Dilutive impact of accounting for awards as equity settled		(1)
Net earnings - diluted	$ 3,293	$ 4,457
Weighted average number of common shares	1,623.0	1,661.0
Dilutive Securities:
Effect of share options	6.0	4.0
Weighted average number of diluted common shares	1,629.0	1,665.0
Basic earnings per share	$ 2.03	$ 2.68
Diluted earnings per share	$ 2.02	$ 2.68

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

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