SHARE-BASED COMPENSATION - Summary of DSU activity (Details) - Deferred share units - shares shares in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of units, beginning of period (in shares)	1,086	1,018
Grants (in shares)	188	150
Exercises (in shares)	0	(82)
Number of units, end of period (in shares)	1,274	1,086

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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- 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 2019-01-01
-Paragraph 47
-Subparagraph b
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_45&doctype=Standard
-URIDate 2019-03-27

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_45&doctype=Standard
-URIDate 2019-03-27

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

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