Non-Operating Income (Expense) - Schedule of Non-Operating Income (Expense) (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Non operating income (expense) [abstract]
Foreign exchange gains	$ 16	$ 5
Gain (loss) on debt prepayment options (Note 28(b))	(42)	51
Gain on sale of investments		9
Loss on debt repurchases (Note 19(a) and Note 19(b))	(26)	(216)
Total non operating income (expense)	$ (52)	$ (151)

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
-Name IAS
-Number 7
-IssueDate 2018-01-01
-Section A Statement of cash flows for an entity other than a financial institution
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2018-03-01&anchor=sect_AStatementofcashflowsforanentityotherthanafinancialinstitution&doctype=Illustrative%20Examples
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 21
-IssueDate 2018-01-01
-Paragraph 52
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=21&date=2018-03-01&anchor=para_52_a&doctype=Standard
-URIDate 2018-03-16

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