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Stock-based Compensation (Performance Share Unit Plan) (Details) - Performance Share Unit Plan - Employee - CAD ($) $ / shares in Units, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Share Unit Plans: Units |  |
Share Unit Plans: Outstanding, Beginning Balance | 1,127,114 |
Share Unit Plans: Granted including DRIP | 545,008 |
Share Unit Plans: Exercised | (140,754) |
Share Unit Plans: Forfeited | 150,268 |
Share Unit Plans: Outstanding and exercisable, Ending Balance | 1,381,100 |
Share Unit Plans: Weighted Average Grant Date Fair Value |  |
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding, Beginning Balance | $ 46.02 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Granted including DRIP | 43.15 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Exercised | 43 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Forfeited | 44.41 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding and exercisable, Ending Balance | $ 45.37 |
Share Unit Plans: Aggregate intrinsic value |  |
Share Unit Plans: Aggregate intrinsic value | $ 88.1 | $ 56.9

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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee exercised the right during the reporting period, in accordance with the terms of the arrangement. + References No definition available. + Details
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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