Goodwill - Schedule of Reconciliation of Changes in Goodwill (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Disclosure of reconciliation of changes in goodwill [line items]
Goodwill	$ 1,556.6
Goodwill	1,621.2	$ 1,556.6
Gross carrying amount [member]
Disclosure of reconciliation of changes in goodwill [line items]
Goodwill	1,734.6	2,006.1
Acquisitions	96.3	16.3
Disposals	(120.2)	(194.4)
Impact of foreign exchange	88.5	(93.4)
Goodwill	1,799.2	1,734.6
Accumulated impairment [member]
Disclosure of reconciliation of changes in goodwill [line items]
Goodwill	(178.0)	(178.0)
Impairment of goodwill	(53.0)
Disposals	53.0
Goodwill	$ (178.0)	$ (178.0)

The amount of additional goodwill recognised, except goodwill included in a disposal group that, on acquisition, meets the criteria to be classified as held for sale in accordance with IFRS 5. [Refer: Goodwill; Disposal groups classified as held for sale [member]]

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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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No definition available.

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The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Business combinations [member]]

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The amount of goodwill derecognised without having previously been included in a disposal group classified as held for sale. [Refer: Goodwill; Disposal groups classified as held for sale [member]]

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The amount of impairment loss recognised in profit or loss for goodwill. [Refer: Impairment loss recognised in profit or loss; Goodwill]

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The increase (decrease) in goodwill resulting from net exchange differences arising on the translation of the financial statements from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Goodwill]

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