Financial risk management (Details 1) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financial risk management [Line Items]
Secured bank loans received	$ 164,780	$ 102,080
Unsecured bank loans received	1,321,640	1,448,210
Borrowings	1,486,420	1,550,290
Derivative financial liabilities held for hedging	9,140	33,950
Derivative financial liabilities held for trading	800	(2,180)
Derivative financial liabilities	9,940	31,770
Financial liabilities	1,496,360	1,582,060
LaterThanOneYear [Member]
Financial risk management [Line Items]
Secured bank loans received	164,780	102,080
Unsecured bank loans received	47,450	94,760
Borrowings	212,230	196,840
Derivative financial liabilities held for hedging	37,010	17,200
Derivative financial liabilities held for trading	800	(2,180)
Derivative financial liabilities	37,810	15,020
Financial liabilities	250,040	211,860
Later than one year and not later than five years [member]
Financial risk management [Line Items]
Secured bank loans received	0	0
Unsecured bank loans received	522,520	479,540
Borrowings	522,520	479,540
Derivative financial liabilities held for hedging	(9,510)	40,330
Derivative financial liabilities held for trading	0	0
Derivative financial liabilities	(9,510)	40,330
Financial liabilities	513,010	519,870
Later than five years [member]
Financial risk management [Line Items]
Secured bank loans received	0	0
Unsecured bank loans received	751,670	873,910
Borrowings	751,670	873,910
Derivative financial liabilities held for hedging	(18,360)	(23,580)
Derivative financial liabilities held for trading	0	0
Derivative financial liabilities	(18,360)	(23,580)
Financial liabilities	733,310	850,330
Gross carrying amount [member]
Financial risk management [Line Items]
Secured bank loans received	163,570	101,270
Unsecured bank loans received	1,054,890	1,130,220
Borrowings	1,218,460	1,231,490
Derivative financial liabilities held for hedging	28,380	42,620
Derivative financial liabilities held for trading	800	(2,175)
Derivative financial liabilities	29,180	40,445
Financial liabilities	$ 1,247,640	$ 1,271,940

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 2017-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard
-URIDate 2017-03-09

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- Definition

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

+ References

+ Details

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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 2017-01-01
-Paragraph 25
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_25&doctype=Standard
-URIDate 2017-03-09

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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 2017-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2017-03-09

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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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- References

No definition available.

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