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Share capital (Schedule of Fair Value Weighted-average Assumptions) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) yr | Sep. 30, 2017 USD ($) yr | Sep. 30, 2018 USD ($) yr | Sep. 30, 2017 USD ($) yr
Disclosure of classes of share capital [abstract] |  |  |  |  |
Expected stock price volatility | [1] |  | 81.00% | 59.00% | 83.00%
Risk free interest rate |  |  | 1.30% | 1.74% | 0.87%
Expected life | yr |  |  | 3 | 3 | 3
Expected forfeiture rate |  |  | 3.67% | 3.36% | 4.18%
Expected dividend yield |  |  | 0.00% | 0.00% | 0.00%
Share-based payments included in cost of sales |  |  |  |  |
Share-based payments included in general and administrative expenses |  | 334 | 278 | 1,711 | 1,241
Total share-based payments |  | $ 334 | $ 278 | $ 1,711 | $ 1,241
[1] | Expected volatility has been based on historical volatility of the Company's publicly traded shares.

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- Definition The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2018-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a_i&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The option life of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2018-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a_i&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2018-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a_i&doctype=Standard -URIDate 2018-03-16 + Details
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- References No definition available. + Details
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- Definition The percentage of an expected dividend used to calculate the fair value of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2018-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2018-03-01&anchor=para_47_a_i&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The percentage of an expected forfeiture rate used to calculate the fair value of share options granted. + References No definition available. + Details
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- Definition Increase (Decrease) Through Share-based Payment Transactions Cost of Sales + References No definition available. + Details
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- Definition Total share-based payments of stock-options. + References No definition available. + Details
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