Share-based compensation - Summary of Share-Based Compensation (Detail) - CAD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based compensation	$ 2	$ 3
Restricted share unit plan [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based compensation	$ 2	$ 3

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.

No definition available.

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