Income Taxes - Summary of Major Components of Current Income Tax Expense from Continuing Operations (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Major components of tax expense (income) [abstract]
Ongoing operations	$ 54.9	$ 64.5
Transition tax related to US tax reform	1.1	(10.0)	$ 31.2
Total current income tax expense	$ 56.0	$ 54.5

The amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 12
-IssueDate 2019-01-01
-Paragraph 80
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_80_a&doctype=Standard
-URIDate 2019-03-27

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