Income Taxes - Summary of Effective Income Tax for Continuing Operations From Statutory Canadian Tax Rates (Detail)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Reconciliation of average effective tax rate and applicable tax rate [abstract]
Income tax expense at statutory Canadian rates	27.00%	27.10%
Increase (decrease) resulting from:
Rate differential on foreign income	2.20%	(3.10%)
Non-deductible expenses and non-taxable income	0.70%	0.80%
Unrecognized tax losses and temporary differences	0.60%	2.00%
Transition tax related to US tax reform	0.40%	(4.40%)
Research and development and other tax credits	(1.00%)	(0.70%)
Other	(3.10%)	2.60%
Average effective tax rate	26.80%	24.30%

The applicable income tax rate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2019-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_c_ii&doctype=Standard
-URIDate 2019-03-27

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The tax expense (income) divided by the accounting profit. [Refer: Accounting profit]

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Tax rate effects, in aggregate, on the reconciliation between the average effective tax rate and the applicable tax rate that the entity does not separately disclose in the reconciliation. [Refer: Average effective tax rate; Applicable tax rate]

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The tax rate effect on the reconciliation between the average effective tax rate and the applicable tax rate resulting from the application of foreign tax rates. [Refer: Average effective tax rate; Applicable tax rate]

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The tax rate effect on the reconciliation between the average effective tax rate and the applicable tax rate resulting from tax losses. [Refer: Average effective tax rate; Applicable tax rate]

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Increase decrease in tax rate.

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Tax rate effect of non deductible expense and non taxable income.

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Tax rate effect of research and development and other tax credits.

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Tax rate effect of transition tax related to tax reform.

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