Financial risk management (Details 1) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial risk management [Line Items]
Bank borrowings	$ 72,340	$ 77,040
Unsecured obligations	2,742,530	2,125,010
Subtotal	2,814,870	2,202,050
Hedging liabilities	29,470	63,270
Derivative financial instruments	5,390	3,170
Subtotal	34,860	66,440
Current and non-current lease liabilities	34,610	42,180
Trade accounts payable and other accounts payable	203,933	205,790
Total	3,088,270	2,516,460
Less than 1 year [member]
Financial risk management [Line Items]
Bank borrowings	940	2,170
Unsecured obligations	88,220	326,340
Subtotal	89,160	328,510
Hedging liabilities	6,060	6,570
Derivative financial instruments	5,390	3,170
Subtotal	11,450	9,740
Current and non-current lease liabilities	6,400	8,900
Trade accounts payable and other accounts payable	203,930	205,790
Total	310,940	552,940
1 to 5 years [member]
Financial risk management [Line Items]
Bank borrowings	71,400	74,870
Unsecured obligations	927,170	614,290
Subtotal	998,570	689,160
Hedging liabilities	12,340	24,330
Derivative financial instruments	0	0
Subtotal	12,340	24,330
Current and non-current lease liabilities	21,040	23,010
Trade accounts payable and other accounts payable	0	0
Total	1,031,950	736,500
Over 5 years [member]
Financial risk management [Line Items]
Bank borrowings	0	0
Unsecured obligations	1,727,140	1,184,380
Subtotal	1,727,140	1,184,380
Hedging liabilities	11,070	32,370
Derivative financial instruments	0	0
Subtotal	11,070	32,370
Current and non-current lease liabilities	7,170	10,270
Trade accounts payable and other accounts payable	0	0
Total	1,745,380	1,227,020
Carrying amount [Member]
Financial risk management [Line Items]
Bank borrowings	70,080	70,190
Unsecured obligations	1,872,090	1,697,110
Subtotal	1,942,170	1,767,300
Hedging liabilities	40,210	23,660
Derivative financial instruments	5,390	3,170
Subtotal	45,600	26,830
Current and non-current lease liabilities	31,070	37,900
Trade accounts payable and other accounts payable	203,930	205,790
Total	$ 2,222,770	$ 2,037,820

The amount of outstanding funds that the entity is obligated to repay.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard
-URIDate 2020-01-01

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Period Type:	instant

- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

+ References

+ Details

Name:	ifrs-full_DerivativeFinancialLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
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- Definition

The amount of derivative financial liabilities held for hedging. [Refer: Derivative financial liabilities]

+ References

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- Definition

The amount of derivative financial liabilities held for trading. [Refer: Derivative financial liabilities; Financial liabilities at fair value through profit or loss that meet definition of held for trading]

+ References

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- Definition

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]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 25
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_25&doctype=Standard
-URIDate 2020-01-01

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- Definition

The amount of loans received from banks that have been secured by collateral. [Refer: Loans received]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2020-01-01

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- Definition

The amount of current trade payables and current other payables. [Refer: Current trade payables; Other current payables]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 54
-Subparagraph k
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_54_k&doctype=Standard
-URIDate 2020-01-01

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- Definition

The amount of loans received from banks that have not been secured by collateral. [Refer: Loans received]

+ References

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- Definition

Current and non-current lease liabilities

+ References

No definition available.

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- References

No definition available.

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