The description of the basis on which the cash-generating unit's (group of units') recoverable amount has been determined (ie value in use or fair value less costs of disposal). [Refer: Cash-generating units [member]]

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The discount rate applied to cash flow projections for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

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The growth rate used to extrapolate cash flow projections beyond the period covered by the most recent budgets/forecasts for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

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The description of the level of the fair value hierarchy within which the fair value measurement is categorised in its entirety (without giving regard to the observability of 'costs of disposal') for a cash-generating unit (group of units'). [Refer: Cash-generating units [member]]

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The explanation of the period over which management has projected cash flows based on financial budgets/forecasts approved by management including, when a period greater than five years is used for a cash-generating unit (group of units), an explanation of why that longer period is justified. [Refer: Cash-generating units [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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Disclosure of goodwill allocated.

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Number of cash generating unit.

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Goodwill - Additional Information (Detail) CAD in Millions		3 Months Ended	12 Months Ended
Goodwill - Additional Information (Detail) CAD in Millions	Oct. 01, 2017	Jun. 30, 2017 CAD	Dec. 31, 2017 CAD Cash_Generating_Units	Oct. 01, 2016
Disclosure of goodwill allocated [line items]
Number of cash generating units			7
Goodwill disposed \| CAD			CAD 194.4
Description of basis on which units recoverable amount has been determined			Using the fair value less costs of disposal approach
Description of level of fair value hierarchy within which fair value measurement is categorised			Level 3
Description of projection	Terminal growth rates based on actual experience and market analysis. Projections are extrapolated beyond five years using a growth rate that does not exceed 3.0%.
Top of range [member]
Disclosure of goodwill allocated [line items]
Discounted Rate	15.10%			13.70%
Percentage of growth rate	3.00%
Bottom of range [member]
Disclosure of goodwill allocated [line items]
Discounted Rate	8.90%			9.00%
Consulting Services Global [member]
Disclosure of goodwill allocated [line items]
Number of cash generating units			3
Goodwill disposed \| CAD		CAD 88.1
Discounted Rate	11.30%
Percentage of growth rate	3.00%
Construction services for allocating goodwill [member]
Disclosure of goodwill allocated [line items]
Number of cash generating units			2
Construction services for impairment testing [member]
Disclosure of goodwill allocated [line items]
Number of cash generating units			2
Consulting Services United States [member]
Disclosure of goodwill allocated [line items]
Goodwill disposed \| CAD		CAD 106.3