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Share Capital (Other employee long-term incentives) (Details) - shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Restricted share units ("RSU") |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 1,666,825 | 1,567,696
Granted | 851,453 | 832,366
Forfeiture | (201,954) | (305,300)
Settled | (347,733) | (427,937)
Shares outstanding | 1,968,591 | 1,666,825
Stock appreciation rights ("SAR") |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 91,307 | 509,192
Granted | 0 | 0
Forfeiture | (13,195) | (309,566)
Settled | (78,112) | (108,319)
Shares outstanding | 0 | 91,307
Deferred share units ("DSU") |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 688,427 | 645,413
Granted | 176,418 | 208,882
Forfeiture | 0 | 0
Settled | 0 | (165,868)
Shares outstanding | 864,845 | 688,427
Performance share units ("PSU") |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 1,082,153 | 983,441
Granted | 475,623 | 423,628
Forfeiture | (75,892) | 0
Settled | (247,866) | (324,916)
Shares outstanding | 1,234,018 | 1,082,153

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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 2020-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
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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 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
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