Non-Operating Income (Expense) - Schedule of Non-Operating Income (Expense) (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Analysis of income and expense [abstract]
Foreign exchange gains (losses)	$ (4)	$ 16
Gain (loss) on debt prepayment option	105	(42)
Loss on debt redemption or purchase (Note 19(a))	(224)	(26)
Other	26	0
Total non operating income (expense)	$ (97)	$ (52)

The amount of exchange differences recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9. [Refer: At fair value [member]; Financial instruments, class [member]]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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