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Fair Value Measurements - Summary of Fair Value Hierarchy for Assets (Detail) - CAD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of fair value measurement of assets [line items] |  |
Other financial assets | $ 144.2 | $ 147.1
Recurring fair value measurement [member] | Investments held for self-insured liabilities [member] |  |
Disclosure of fair value measurement of assets [line items] |  |
Other financial assets | 144.2 |
Recurring fair value measurement [member] | Significant other observable inputs [member] | Investments held for self-insured liabilities [member] |  |
Disclosure of fair value measurement of assets [line items] |  |
Other financial assets | $ 144.2 |

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- Definition The amount of financial assets that the entity does not separately disclose in the same statement or note. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_d&doctype=Standard -URIDate 2018-03-16 + Details
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