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Goodwill (Details) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Goodwill [Roll Forward] |  |
Balance, January 1 | $ 5,835 | $ 6,313
Additions | 0 | 3
GBPC impairment charge | 0 | (30)
Classified as assets held for sale | 0 | (148)
Change in foreign exchange rate | (115) | (303)
Balance, December 31 | 5,720 | 5,835
GBPC |  |
Goodwill [Roll Forward] |  |
Balance, January 1 | 70 |
GBPC impairment charge |  | (30)
Balance, December 31 | $ 68 | $ 70

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