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Inventories - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Write-downs (reversals of write-downs) of inventories [abstract] |  |
Inventory write-down | $ 11,376 | $ 405
Purchase Commitments And Collateral [Abstract] |  |
Inventories secured | $ 314,067 |

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- Definition The amount of inventories pledged as security for liabilities. [Refer: Inventories] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 2 -IssueDate 2018-01-01 -Paragraph 36 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=2&date=2018-03-01&anchor=para_36_h&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of expense recognised related to the write-down of inventories to net realisable value. [Refer: Inventories] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 2 -IssueDate 2018-01-01 -Paragraph 36 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=2&date=2018-03-01&anchor=para_36_e&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 98 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_98_a&doctype=Standard -URIDate 2018-03-16 + Details
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