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Tax Matters - Current Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Current tax assets |  |
Income tax receivable | $ 27,404 | $ 17,158
Current tax liabilities |  |
Income tax payable | 2,335 | 7,419
Net tax assets | $ 25,069 | $ 9,739

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- Definition The excess of amount paid for current tax in respect of current and prior periods over the amount due for those periods net of the amount of current tax for current and prior periods to the extent unpaid. Current tax is the amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period. + References No definition available. + Details
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- Definition The excess of amount paid for current tax in respect of current and prior periods over the amount due for those periods. Current tax is the amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph n -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_n&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of current tax for current and prior periods to the extent unpaid. Current tax is the amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph n -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_n&doctype=Standard -URIDate 2018-03-16 + Details
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