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v3.19.3.a.u2

Asset Impairment Charges and Reversals (Details) - CAD ($) $ in Millions |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jun. 28, 2018 | Dec. 31, 2019 | Jun. 30, 2017 | Sep. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2016 | Dec. 31, 2012
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Write-downs (reversals of write-downs) of property, plant and equipment |  |  |  |  | $ 18 | $ 23 |  |
Disposal groups classified as held for sale |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss |  | $ 15 |  |  |  |  |  |
Sundance Unit 2 |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss |  |  |  | $ 38 |  |  |  |
Lakeswind |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss | $ 12 |  |  |  |  |  |  |
Sundance Unit 1 |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss |  |  | $ 20 |  |  |  |  |
Wintering Hills | Wind and Solar |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Decrease through classified as held for sale, investment property |  |  |  |  |  |  | $ 28 |
Property, plant and equipment | Centralia Plant CGU |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss |  |  |  |  |  |  |  | $ 347
Reversal of impairment loss |  |  |  |  | 151 |  |  |
Provision for decommissioning, restoration and rehabilitation costs |  | $ 141 |  |  | $ 141 |  |  |
Property, plant and equipment | Lakeswind |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss | 11 |  |  |  |  |  |  |
Intangible assets | Lakeswind |  |  |  |  |  |  |  |
Disclosure of impairment loss recognised or reversed [line items] |  |  |  |  |  |  |  |
Impairment loss | $ 1 |  |  |  |  |  |  |

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- Definition The decrease in investment property through classification as held for sale or inclusion in a disposal group classified as held for sale. [Refer: Disposal groups classified as held for sale [member]; Property, plant and equipment; Investment property; Disposal groups classified as held for sale [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2018-01-01 -Paragraph 76 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_76_c&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 40 -IssueDate 2018-01-01 -Paragraph 79 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2018-03-01&anchor=para_79_d_iii&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount recognised as a reduction of the carrying amount of an asset or cash-generating unit to its recoverable amount. [Refer: Carrying amount [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2018-01-01 -Paragraph 130 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2018-03-01&anchor=para_130_b&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 36 -IssueDate 2018-01-01 -Paragraph 130 -Subparagraph d -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2018-03-01&anchor=para_130_d_ii&doctype=Standard -URIDate 2018-03-16 + Details
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