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Stock-based Compensation (Deferred Share Unit Plans) (Details) - DSU Plan - Deferred Share Unit Plans | 12 Months Ended
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Dec. 31, 2019 $ / shares shares
Employee |
Share Unit Plans: Units |
Share Unit Plans: Outstanding, Beginning Balance | shares | 837,109
Share Unit Plans: Granted including DRIP | shares | 120,098
Share Unit Plans: Exercised | shares | (252,610)
Share Unit Plans: Outstanding and exercisable, Ending Balance | shares | 704,597
Share Unit Plans: Weighted Average Grant Date Fair Value |
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding, Beginning Balance | $ / shares | $ 29.54
Share Unit Plans: Weighted Average Grant Date Fair Value: Granted including DRIP | $ / shares | 39.05
Share Unit Plans: Weighted Average Grant Date Fair Value: Exercised | $ / shares | 19.68
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding and exercisable, Ending Balance | $ / shares | $ 34.69
Director |
Share Unit Plans: Units |
Share Unit Plans: Outstanding, Beginning Balance | shares | 563,521
Share Unit Plans: Granted including DRIP | shares | 104,293
Share Unit Plans: Exercised | shares | (136,360)
Share Unit Plans: Outstanding and exercisable, Ending Balance | shares | 531,454
Share Unit Plans: Weighted Average Grant Date Fair Value |
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding, Beginning Balance | $ / shares | $ 37.07
Share Unit Plans: Weighted Average Grant Date Fair Value: Granted including DRIP | $ / shares | 42.25
Share Unit Plans: Weighted Average Grant Date Fair Value: Exercised | $ / shares | 29.76
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding and exercisable, Ending Balance | $ / shares | $ 39.96

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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 The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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