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v3.19.1

Tax matters - Significant components of deferred tax assets and liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Deferred tax assets | $ 14,589 | $ 5,273
Deferred tax liabilities | 77,379 | 65,142
Net Total Deferred Tax Asset / (Liability) | (62,790) | (59,869)
Total | $ 483,459 | 465,663
Number of years open to review | 4 years |
Unused tax losses |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Total | $ 396,119 | 391,997
Unused tax credits |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Total | 7,963 | 8,028
Unrecognised deductible temporary differences |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Total | 79,377 | 65,638
Hedging instruments |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Net Total Deferred Tax Asset / (Liability) | 1,010 | 1,239
Other |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |
Net Total Deferred Tax Asset / (Liability) | $ (678) | $ (6,028)

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- Definition The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2018-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2018-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2018-03-16 + Details
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