Investments (Details) - CAD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Rail investments accounted for on an equity basis	$ 150	$ 166
Other investments	49	48
Total investments	199	341
CMQ
Schedule of Equity Method Investments [Line Items]
Rail investments accounted for on an equity basis	$ 0	$ 127

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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