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Segment Disclosures Disclosure of operating segments (Details) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of operating segments [line items] |  |  |
Revenues | $ 2,347 | $ 2,249 | $ 2,307
Fuel and purchased power (Note 6) | 1,086 | 1,100 | 1,016
Gross margin | 1,261 | 1,149 | 1,291
Depreciation and amortization | 590 | 574 | 635
Asset impairment charges (reversals) (Note 7) | 25 | 73 | 20
Gains on termination of investments | 56 | 157 | 0
Taxes, other than income taxes | 29 | 31 | 30
Finance lease income | 6 | 8 | 54
Gain on sale of assets and other (Note 4(D) and 17) | 46 | 1 | 2
Net interest expense (Note 10) | (179) | (250) | (247)
Foreign exchange loss | (15) | (15) | (1)
Earnings (loss) before income taxes | 193 | (96) | (54)
Goodwill | 464 | 464 |
Property, plant and equipment | 6,207 | 6,164 | 6,578
Right-of-use assets | 146 | 0 |
Intangible assets | 318 | 373 | 364
Other assets | 198 | 234 |
Property, plant and equipment expenditures | 417 | 277 | 338
Purchase of intangible assets | 14 | 20 | 51
Mine depreciation | 119 | 136 | 73
Adjustments for depreciation and amortisation expense | 709 | 710 | 708
Canada |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 1,460 | 1,573 | 1,663
Goodwill | 418 | 417 |
Property, plant and equipment | 4,854 | 4,953 |
Right-of-use assets | 109 | 0 |
Intangible assets | 213 | 273 |
Other assets | 75 | 101 |
US |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 727 | 511 | 509
Goodwill | 46 | 47 |
Property, plant and equipment | 863 | 657 |
Right-of-use assets | 33 | 0 |
Intangible assets | 68 | 59 |
Other assets | 47 | 50 |
Australia |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 160 | 165 | 135
Goodwill | 0 | 0 |
Property, plant and equipment | 490 | 554 |
Right-of-use assets | 4 | 0 |
Intangible assets | 37 | 41 |
Other assets | 76 | 83 |
Reportable segments [member] |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 2,347 | 2,249 | 2,307
Fuel and purchased power (Note 6) | 1,086 | 1,100 | 1,016
Gross margin | 1,261 | 1,149 | 1,291
Operations, maintenance, and administration (Note 5) | 475 | 515 | 517
Depreciation and amortization | 590 | 574 | 635
Asset impairment charges (reversals) (Note 7) | 25 | 73 | 20
Gains (losses) on disposals of investments | (88) |  |
Gains on termination of investments | 56 | 157 |
Taxes, other than income taxes | 29 | 31 | 30
Profit (loss) from operating activities | (49) | (47) | (49)
Operating income | 335 | 160 | 138
Finance lease income | 6 | 8 | 54
Gain on sale of assets and other (Note 4(D) and 17) | 46 | 1 | 2
Net interest expense (Note 10) | (179) | (250) | (247)
Foreign exchange loss | (15) | (15) | (1)
Earnings (loss) before income taxes | 193 | (96) | (54)
Goodwill | 464 | 464 |
Property, plant and equipment | 6,207 | 6,164 |
Right-of-use assets | 146 |  |
Intangible assets | 318 | 373 |
Property, plant and equipment expenditures | 417 | 277 | 338
Purchase of intangible assets | 14 | 20 | 51
Reportable segments [member] | Canadian Coal |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 816 | 912 | 999
Fuel and purchased power (Note 6) | 570 | 666 | 585
Gross margin | 246 | 246 | 414
Operations, maintenance, and administration (Note 5) | 138 | 171 | 192
Depreciation and amortization | 233 | 241 | 317
Asset impairment charges (reversals) (Note 7) | 15 | 38 | 20
Gains (losses) on disposals of investments | (88) |  |
Gains on termination of investments | 56 | 157 |
Taxes, other than income taxes | 13 | 13 | 13
Profit (loss) from operating activities | (40) | (41) | (40)
Operating income | 31 | (19) | (88)
Finance lease income | 0 | 0 | 0
Goodwill | 0 | 0 |
Property, plant and equipment | 2,540 | 2,587 |
Right-of-use assets | 68 |  |
Intangible assets | 41 | 81 |
Property, plant and equipment expenditures | 114 | 101 | 116
Purchase of intangible assets | 2 | 3 | 5
Reportable segments [member] | United States Coal |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 571 | 442 | 435
Fuel and purchased power (Note 6) | 416 | 314 | 293
Gross margin | 155 | 128 | 142
Operations, maintenance, and administration (Note 5) | 67 | 61 | 51
Depreciation and amortization | 83 | 74 | 73
Asset impairment charges (reversals) (Note 7) | (10) | 0 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 3 | 5 | 4
Profit (loss) from operating activities | 0 | 0 | 0
Operating income | 12 | (12) | 14
Finance lease income | 0 | 0 | 0
Goodwill | 0 | 0 |
Property, plant and equipment | 352 | 332 |
Right-of-use assets | 0 |  |
Intangible assets | 6 | 7 |
Property, plant and equipment expenditures | 8 | 14 | 35
Purchase of intangible assets | 0 | 0 | 1
Reportable segments [member] | Canadian Gas |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 209 | 232 | 261
Fuel and purchased power (Note 6) | 74 | 96 | 101
Gross margin | 135 | 136 | 160
Operations, maintenance, and administration (Note 5) | 44 | 48 | 50
Depreciation and amortization | 41 | 43 | 38
Asset impairment charges (reversals) (Note 7) | 0 | 0 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 1 | 1 | 1
Profit (loss) from operating activities | (1) | 0 | (9)
Operating income | 50 | 44 | 80
Finance lease income | 6 | 8 | 11
Goodwill | 0 | 0 |
Property, plant and equipment | 392 | 391 |
Right-of-use assets | 0 |  |
Intangible assets | 2 | 4 |
Property, plant and equipment expenditures | 36 | 21 | 31
Purchase of intangible assets | 0 | 0 | 0
Reportable segments [member] | Australian Gas |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 160 | 165 | 135
Fuel and purchased power (Note 6) | 9 | 8 | 14
Gross margin | 151 | 157 | 121
Operations, maintenance, and administration (Note 5) | 37 | 37 | 31
Depreciation and amortization | 48 | 49 | 37
Asset impairment charges (reversals) (Note 7) | 0 | 0 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 0 | 0 | 0
Profit (loss) from operating activities | 0 | 0 | 0
Operating income | 66 | 71 | 53
Finance lease income | 0 | 0 | 43
Goodwill | 0 | 0 |
Property, plant and equipment | 489 | 554 |
Right-of-use assets | 4 |  |
Intangible assets | 37 | 41 |
Property, plant and equipment expenditures | 6 | 6 | 114
Purchase of intangible assets | 0 | 0 | 29
Reportable segments [member] | Wind and Solar |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 312 | 282 | 287
Fuel and purchased power (Note 6) | 16 | 17 | 17
Gross margin | 296 | 265 | 270
Operations, maintenance, and administration (Note 5) | 50 | 50 | 48
Depreciation and amortization | 124 | 110 | 111
Asset impairment charges (reversals) (Note 7) | 0 | 12 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 8 | 8 | 8
Profit (loss) from operating activities | (10) | (6) | 0
Operating income | 124 | 91 | 103
Finance lease income | 0 | 0 | 0
Goodwill | 176 | 175 |
Property, plant and equipment | 1,947 | 1,799 |
Right-of-use assets | 56 |  |
Intangible assets | 173 | 173 |
Property, plant and equipment expenditures | 229 | 117 | 20
Purchase of intangible assets | 0 | 0 | 0
Reportable segments [member] | Hydro |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 156 | 156 | 121
Fuel and purchased power (Note 6) | 7 | 6 | 6
Gross margin | 149 | 150 | 115
Operations, maintenance, and administration (Note 5) | 36 | 38 | 37
Depreciation and amortization | 32 | 30 | 31
Asset impairment charges (reversals) (Note 7) | 2 | 0 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 3 | 3 | 3
Profit (loss) from operating activities | 0 | 0 | 0
Operating income | 76 | 79 | 44
Finance lease income | 0 | 0 | 0
Goodwill | 258 | 259 |
Property, plant and equipment | 469 | 481 |
Right-of-use assets | 6 |  |
Intangible assets | 5 | 4 |
Property, plant and equipment expenditures | 23 | 16 | 16
Purchase of intangible assets | 0 | 0 | 0
Reportable segments [member] | Energy Marketing |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | 129 | 67 | 69
Fuel and purchased power (Note 6) | 0 | 0 | 0
Gross margin | 129 | 67 | 69
Operations, maintenance, and administration (Note 5) | 30 | 24 | 24
Depreciation and amortization | 2 | 2 | 2
Asset impairment charges (reversals) (Note 7) | 0 | 0 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 0 | 0 | 0
Profit (loss) from operating activities | 0 | 0 | 0
Operating income | 97 | 41 | 43
Finance lease income | 0 | 0 | 0
Goodwill | 30 | 30 |
Property, plant and equipment | 1 | 1 |
Right-of-use assets | 0 |  |
Intangible assets | 9 | 11 |
Property, plant and equipment expenditures | 0 | 0 | 0
Purchase of intangible assets | 0 | 0 | 0
Reportable segments [member] | Corporate |  |  |
Disclosure of operating segments [line items] |  |  |
Revenues | (6) | (7) | 0
Fuel and purchased power (Note 6) | (6) | (7) | 0
Gross margin | 0 | 0 | 0
Operations, maintenance, and administration (Note 5) | 73 | 86 | 84
Depreciation and amortization | 27 | 25 | 26
Asset impairment charges (reversals) (Note 7) | 18 | 23 | 0
Gains (losses) on disposals of investments | 0 |  |
Gains on termination of investments | 0 | 0 |
Taxes, other than income taxes | 1 | 1 | 1
Profit (loss) from operating activities | 2 | 0 | 0
Operating income | (121) | (135) | (111)
Finance lease income | 0 | 0 | 0
Goodwill | 0 | 0 |
Property, plant and equipment | 17 | 19 |
Right-of-use assets | 12 |  |
Intangible assets | 45 | 52 |
Property, plant and equipment expenditures | 1 | 2 | 6
Purchase of intangible assets | $ 12 | $ 17 | $ 16

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