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- Definition

The amount of contingent liabilities recognised in a business combination. [Refer: Contingent liabilities [member]; Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B67
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_B67_c&doctype=Appendix&seq=2
-URIDate 2017-03-09

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- Definition

The amount of current derivative financial liabilities. [Refer: Derivative financial liabilities]

+ References

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 fair value of financial instruments designated as hedging instruments. Hedging instruments are designated derivatives or (for a hedge of the risk of changes in foreign currency exchange rates only) designated non-derivative financial assets or non-derivative financial liabilities whose fair value or cash flows are expected to offset changes in the fair value or cash flows of a designated hedged item. [Refer: At fair value [member]; Derivatives [member]; Derivative financial assets; Derivative financial liabilities; Financial instruments, class [member]; Financial assets; Financial liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 22
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_22_b&doctype=Standard&book=B
-URIDate 2017-03-09

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Fair value measurement (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair value measurement liabilities [Abstract]
- Embedded derivatives for concentrates sales, net	$ 0	$ 1,524
- Contingent consideration liability	17,570	19,343	$ 16,994	$ 23,026
- Hedge instruments	28,705	(3,863)
Level 1 of fair value hierarchy [member]
Fair value measurement liabilities [Abstract]
- Embedded derivatives for concentrates sales, net	0	0
- Contingent consideration liability	0	0
- Hedge instruments	0	0
Level 2 of fair value hierarchy [member]
Fair value measurement liabilities [Abstract]
- Embedded derivatives for concentrates sales, net	7,424	1,524
- Contingent consideration liability	0	0
- Hedge instruments	28,705	3,863
Level 3 of fair value hierarchy [member]
Fair value measurement liabilities [Abstract]
- Embedded derivatives for concentrates sales, net	0	0
- Contingent consideration liability	17,570	19,343
- Hedge instruments	$ 0	$ 0