Financial instruments (Details 29) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	$ 494,736	$ 179,205
Current, total financial liabilities	505,087	187,345
Non-current financial liabilities at fair value through profit or loss	1,502,449	1,318,349
Non-current, total financial liabilities		1,330,382
Financial liabilities at fair value through profit or loss	0	91
Total, total financial liabilities	1,518,926	1,517,727
Lease Liability [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	7,694
Non-current financial liabilities at fair value through profit or loss	30,203
Financial liabilities at fair value through profit or loss	37,897
Trade payables due to related parties [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	475	9
Financial liabilities at fair value through profit or loss	475	9
Financial liabilities at fair value through profit or loss [Member]
Financial instruments [Line Items]
Current financial liabilities at amortised cost	10,351	8,140
Non-current financial liabilities at amortised cost	16,477	12,033
Financial liabilities at amortised cost	26,828	20,173
Bank borrowings [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	199	300
Non-current financial liabilities at fair value through profit or loss	69,138	68,870
Financial liabilities at fair value through profit or loss	69,337	69,170
Bonds issued [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	280,578	15,145
Non-current financial liabilities at fair value through profit or loss	1,403,108	1,249,479
Financial liabilities at fair value through profit or loss	1,683,686	1,264,624
Trade and other payables [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	205,790	163,751
Non-current financial liabilities at fair value through profit or loss	0	0
Financial liabilities at fair value through profit or loss	205,790	163,751
Hedging liabilities [Member]
Financial instruments [Line Items]
Current financial liabilities at amortised cost	7,183	5,285
Non-current financial liabilities at amortised cost	16,477	12,033
Financial liabilities at amortised cost	23,660	17,318
Financial assets at fair value through profit or loss, classified as held for trading, category [member]
Financial instruments [Line Items]
Current financial liabilities at amortised cost	3,168	2,855
Non-current financial liabilities at amortised cost	0	0
Financial liabilities at amortised cost	$ 3,168	$ 2,855

The amount of current financial liabilities. [Refer: Financial liabilities]

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The amount of current financial liabilities measured at amortised cost. [Refer: Financial liabilities at amortised cost]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of current financial liabilities measured at fair value through profit or loss. [Refer: Financial liabilities at fair value through profit or loss]

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The amount of financial liabilities at amortised cost. The amortised cost is the amount at which financial liabilities are measured at initial recognition minus principal repayments, plus or minus the cumulative amortisation using the effective interest method of any difference between that initial amount and the maturity amount. [Refer: Financial liabilities]

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The amount of financial liabilities that meet either of the following conditions: (a) they meet the definition of held for trading; or (b) upon initial recognition they are designated by the entity as at fair value through profit or loss. An entity may use this designation only when permitted by paragraph 4.3.5 of IFRS 9 (embedded derivatives) or when doing so results in more relevant information, because either: (a) it eliminates or significantly reduces a measurement or recognition inconsistency (sometimes referred to as ‘an accounting mismatch’) that would otherwise arise from measuring assets or liabilities or recognising the gains and losses on them on different bases; or (b) a group of financial liabilities or financial assets and financial liabilities is managed and its performance is evaluated on a fair value basis, in accordance with a documented risk management or investment strategy, and information about the group is provided internally on that basis to the entity’s key management personnel (as defined in IAS 24). [Refer: At fair value [member]; Key management personnel of entity or parent [member]; Derivatives [member]; Financial assets; Financial liabilities]

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The amount of non-current financial liabilities. [Refer: Financial liabilities]

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