segment information - Geographical information (Details) - CAD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2017
Disclosure of operating segments
Goodwill	$ 4,733	$ 4,236	$ 3,787
Foreign
Disclosure of operating segments
Goodwill	$ 546	$ 262

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]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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