Financial instruments (Details 27) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	$ 179,205,000	$ 374,707
Current, total financial liabilities	187,345,000	417,973,000
Non-current financial liabilities at fair value through profit or loss		1,031,507,000
Non-current, total financial liabilities		1,031,507,000
Financial liabilities at fair value through profit or loss	1,497,554,000	1,406,214	$ 0
Total, total financial liabilities	1,733,080,000	1,496,360,000
Financial liabilities at fair value through profit or loss [Member]
Financial instruments [Line Items]
Current financial liabilities at amortised cost	8,140,000	43,266
Non-current financial liabilities at amortised cost		0
Financial liabilities at amortised cost	20,173,000	43,266
Total, total financial liabilities	2,855,000	5,979,000
Bank borrowings [Member]
Financial instruments [Line Items]
Current financial liabilities at amortised cost	163,568,000	163,568,000
Current financial liabilities at fair value through profit or loss	300,000	163,568,000
Non-current financial liabilities at fair value through profit or loss		0
Total, total financial liabilities	69,170,000	163,568,000
Bonds issued [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	15,145,000	13,494,000
Non-current financial liabilities at fair value through profit or loss		1,031,507,000
Total, total financial liabilities	1,264,624,000	1,045,001,000
Trade and other payables [Member]
Financial instruments [Line Items]
Current financial liabilities at fair value through profit or loss	163,751,000	196,280,000
Non-current financial liabilities at fair value through profit or loss		0
Total, total financial liabilities	163,751,000	196,280,000
Hedging liabilities [Member]
Financial instruments [Line Items]
Current financial liabilities at amortised cost	5,285,000	37,287,000
Non-current financial liabilities at amortised cost		0
Financial liabilities at amortised cost	17,318,000	37,287,000
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	2,855,000	5,979,000
Non-current financial liabilities at amortised cost		0
Financial liabilities at amortised cost	$ 2,855,000	$ 5,979,000

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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
-Name IFRS
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Reference 2: 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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-Name IFRS
-Number 7
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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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The amount of non-current financial liabilities measured at amortised cost. [Refer: Financial liabilities at amortised cost]

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The amount of non-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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