Income tax and deferred taxes (Details 7) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Disclosure of Income tax and deferred taxes [Line Items]
Deferred tax liability (asset) at beginning of period	$ 205,455	$ 219,230
Increase (decrease) in deferred taxes in profit or loss	(440)	(14,624)
Increase (decrease) in deferred taxes in equity	268	849
Deferred tax liability (asset) at end of period	$ 205,283	$ 205,455

The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
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- Definition

The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
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The amount of deferred tax related to items credited (charged) directly to equity. [Refer: Deferred tax expense (income)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References

No definition available.

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