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Share Capital (Other employee long-term incentives) (Details) - shares | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Restricted share units (RSU) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 1,567,696 | 1,500,934
Granted | 832,366 | 611,717
Forfeiture | (305,300) | (99,939)
Settled | (427,937) | (445,016)
Shares outstanding | 1,666,825 | 1,567,696
Stock appreciation rights (SAR) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 509,192 | 1,055,525
Granted | 0 | 0
Forfeiture | (309,566) | (482,533)
Settled | (108,319) | (63,800)
Shares outstanding | 91,307 | 509,192
Deferred share units (DSU) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 645,413 | 480,605
Granted | 208,882 | 164,808
Forfeiture | 0 | 0
Settled | (165,868) | 0
Shares outstanding | 688,427 | 645,413
Performance share units (PSU) |  |
Disclosure of classes of share capital [line items] |  |
Shares outstanding | 983,441 | 599,705
Granted | 423,628 | 440,420
Forfeiture | 0 | (56,684)
Settled | (324,916) | 0
Shares outstanding | 1,082,153 | 983,441

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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 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_b&doctype=Standard -URIDate 2019-03-27 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 + 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 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 + Details
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