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Stock-Based Compensation (Summary of Activity Related to Employee Restricted Share Units) (Details) - Restricted Share Unit Plan - Employee - CAD ($) $ / shares in Units, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023
Share Unit Plans: Units |  |
Share Unit Plans: Outstanding, Beginning Balance | 562,641 |
Share Unit Plans: Granted including DRIP | 287,976 |
Share Unit Plans: Exercised | (183,241) |
Share Unit Plans: Forfeited | (14,228) |
Share Unit Plans: Outstanding and exercisable, Ending Balance | 653,148 |
Share Unit Plans: Weighted Average Grant Date Fair Value |  |
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding, Beginning Balance | $ 55.01 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Granted including DRIP | 48.65 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Exercised | 54.66 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Forfeited | 52.45 |
Share Unit Plans: Weighted Average Grant Date Fair Value: Outstanding and exercisable, Ending Balance | $ 52.36 |
Share Unit Plans: Aggregate intrinsic value |  |
Share Unit Plans: Aggregate intrinsic value | $ 41 | $ 32

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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://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(03) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + 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://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + 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://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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