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v3.21.1

Employee Benefit Plans (Change in AOCI and Regulatory Assets) (Details) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Defined benefit pension plans |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | $ 517 |
Amortized in current period | 15 | $ 16
Ending Balance | 439 | 517
Defined benefit pension plans | Regulatory | Assets |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | 358 |
Amortized in current period | (25) |
Current year addition to AOCI or regulatory assets | (12) |
Current year change due to divestitures | (39) |
Foreign currency translation adjustment | (3) |
Ending Balance | 279 | 358
Defined benefit pension plans | Actuarial losses (gains) | Assets |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | 160 |
Amortized in current period | (15) |
Current year addition to AOCI or regulatory assets | 14 |
Foreign currency translation adjustment | 1 |
Ending Balance | 160 | 160
Defined benefit pension plans | Past service costs (gains) | Assets |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | (1) |
Amortized in current period | 1 |
Current year addition to AOCI or regulatory assets | 0 |
Foreign currency translation adjustment | 0 |
Ending Balance | 0 | (1)
Non-pension Benefit Plans |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | 73 |
Amortized in current period | 0 | 0
Ending Balance | 106 | 73
Non-pension Benefit Plans | Regulatory | Assets |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | 78 |
Amortized in current period | 0 |
Current year addition to AOCI or regulatory assets | 48 |
Current year change due to divestitures | (13) |
Foreign currency translation adjustment | (3) |
Ending Balance | 110 | 78
Non-pension Benefit Plans | Actuarial losses (gains) | Assets |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | (5) |
Amortized in current period | 0 |
Current year addition to AOCI or regulatory assets | 2 |
Foreign currency translation adjustment | (1) |
Ending Balance | (4) | (5)
Non-pension Benefit Plans | Past service costs (gains) | Assets |  |
Change in AOCI and Regulatory Assets |  |
Beginning Balance | 0 |
Amortized in current period | 0 |
Current year addition to AOCI or regulatory assets | 0 |
Foreign currency translation adjustment | 0 |
Ending Balance | $ 0 | $ 0

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