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v3.21.1

Accumulated Other Comprehensive Income (Loss) (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) $ in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 CAD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 CAD ($) | Dec. 31, 2019 USD ($)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Total operating revenues | $ 5,506 |  | $ 6,111 |
Other income net (note 9) | 708 |  | 12 |
Operating, maintenance and general | 1,419 |  | 1,464 |
Income tax expense (recovery) | 341 |  | 61 |
Net income | 984 |  | 710 |
Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Net income | 1 |  | 77 |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Losses (gain) on derivatives recognized as cash flow hedges |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Total operating revenues | 2 |  | 3 |
Total before tax | 2 |  | 3 |
Net income | 2 |  | 3 |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net change in unrecognized pension and post-retirement benefit costs |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Pension and post-retirement benefits | (16) |  | 39 |
Regulatory assets |  | $ 0 |  | $ 28
Total before tax | (2) |  | 83 |
Income tax expense (recovery) | 1 |  | (9) |
Net income | $ (1) |  | $ 74 |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Actuarial losses (gains) |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Other income net (note 9) |  | 15 |  | 17
Reclassification out of Accumulated Other Comprehensive Income [Member] | Past service costs (gains) |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Other income net (note 9) |  | $ (1) |  | $ (1)

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