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v3.19.1

Share-based compensation - Weighted average assumptions (Details) - SARs and TSARs | 12 Months Ended
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Dec. 31, 2018 USD ($) year | Dec. 31, 2017 USD ($) year
Disclosure of terms and conditions of share-based payment arrangement [line items] |  |
Risk-free interest rate | 2.60% | 1.80%
Expected dividend yield | 2.70% | 2.00%
Expected life of SARs and TSARs (years) | year | 1.5 | 1.2
Expected volatility | 35.00% | 31.00%
Expected forfeitures | 0.20% | 0.20%
Weighted average fair value (USD per share) | $ | $ 7.93 | $ 19.02

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2017-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_b&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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