Share-based payments - Outstanding RSUs/PSUs Activity (Details) - Restricted share units (RSUs) and performance share units (PSUs)	6 Months Ended
Jun. 30, 2018 CAD ($) shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Outstanding, January 1, 2018 (in shares)	2,740,392
Granted (in shares)	958,411
Dividends credited (in shares)	71,863
Settled (in shares)	(1,010,626)
Forfeited (in shares)	(20,287)
Outstanding, June 30, 2018 (in shares)	2,739,753
Weighted average fair value at measurement date, other equity instruments granted \| $	$ 57

Number Of Other Equity Instruments Dividends Credited Share-Based Payment Arrangement

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- Definition

Number Of Other Equity Instruments Settled In Share-Based Payment Arrangement

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph b
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-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
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-URIDate 2017-03-09

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- Definition

The number of other equity instruments (ie other than share options) forfeited in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard
-URIDate 2017-03-09

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- Definition

The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement.

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- Definition

The weighted average fair value at the measurement date of granted equity instruments other than share options. [Refer: Weighted average [member]]

+ References

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