Income Taxes - Summary of Effective Income Tax for Continuing Operations From Statutory Canadian Tax Rates (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Income taxes [Abstract]
Income tax expense at statutory Canadian rates	25.60%	27.00%
Increase (decrease) resulting from:
Rate differential on foreign income	2.50%	2.20%
Non-deductible expenses and non-taxable income	1.60%	0.70%
Unrecognized tax losses and temporary differences	(0.50%)	0.60%
Research and development and other tax credits	(1.10%)	(1.00%)
Other	(1.50%)	(2.70%)
Average effective tax rate	26.60%	26.80%

The applicable income tax rate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2020-en-r&anchor=para_81_c_ii&doctype=Standard
-URIDate 2020-01-01

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- Definition

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 expenses not deductible in determining taxable profit. [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 revenue that is exempt from taxation. [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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- Definition

Income taxes

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