Business Acquisitions - Additional Information (Detail) - Aggregated individually immaterial business combinations [member] CAD in Millions	12 Months Ended
Dec. 31, 2017 CAD
Disclosure of detailed information about business combination [line items]
Fair value of trade receivables	CAD 7.9
Gross value of trade receivables	8.2
Goodwill is deductible for income tax purposes	22.3
Provisions	0.2
Provision for claims outstanding	17.0
Gross revenue earned	19.8
Gross revenue from continuing operations	5,176.8
Profit from continuing operations	98.3
Acquisition-related costs	CAD 0.4

The amount of acquisition-related costs recognised as an expense for transactions that are recognised separately from the acquisition of assets and the assumption of liabilities in business combinations. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2017-01-01
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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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The fair value of receivables acquired in a business combination. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B64
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The gross contractual amounts receivable for receivables acquired in business combinations. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B64
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- Definition

The profit (loss) of the combined entity as though the acquisition date for all business combinations that occurred during the year had been as of the beginning of the annual reporting period. [Refer: Business combinations [member]; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of revenue of the acquiree since the acquisition date included in the consolidated statement of comprehensive income. [Refer: Revenue]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The revenue of the combined entity as though the acquisition date for all business combinations that occurred during the year had been as of the beginning of the annual reporting period. [Refer: Business combinations [member]; Revenue]

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Goodwill and intangible assets expected deductible for tax purposes.

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Outstanding provisions reassessed and arised based on expected probable outcome.

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Provisions for claims recognised as of acquisition date.

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