Stock-Based Compensation Plans - Additional Information (Detail) shares in Thousands	6 Months Ended
Jun. 30, 2019 CAD ($) shares	Dec. 31, 2018 shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Common shares issued for settlement	13	0
NSRs [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Weighted average exercise price \| $	$ 22.79
Weighted average exercise price of shares exercised \| $	$ 9.48
Number of units exercised	59
Common shares issued for settlement	13

Number of common shares issued under stock option plan.

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.

+ Details

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- Definition

The number of share options exercised in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_iv&doctype=Standard
-URIDate 2018-03-16

+ Details

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- Definition

The weighted average exercise price of share options exercised in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

+ Details

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- Definition

The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_i&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2018-01-01
-Paragraph 45
-Subparagraph b
-Clause vi
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_45_b_vi&doctype=Standard
-URIDate 2018-03-16

+ Details

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- Details

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