Other (Income) Expense - Other Income and Expense (Details) - CAD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Other Income and Expenses [Abstract]
Foreign exchange gain on debt and lease liabilities	$ 0	$ (33)
Other foreign exchange (gains) losses	(2)	1
Acquisition-related costs	0	3
Other	1	1
Other income	$ (1)	$ (28)