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Other financial Liabilities - Interest rate swaps (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Other financial liabilities |  |
Valuation adjustments reserve related to hedging relationship for which hedge accounting no longer applied | $ 2,602 |
Market value | (3,079) | $ (4,392)
Derivatives [member] |  |
Other financial liabilities |  |
Nominal Amount | 23,463 | 38,040
Later Than Six Years And Not Later Seven Years [Member] | Lease Of Hydroelectrical Installations [Member] |  |
Other financial liabilities |  |
Nominal Amount |  | $ 143,916
Fixed Interest Rate |  | 2.05%
Reference Floating Interest Rate |  | 6-month Euribor
Market value | (3,079) | $ (4,392)
Later Than Six Years And Not Later Seven Years [Member] | Lease Of Hydroelectrical Installations [Member] | Fixed rate |  |
Other financial liabilities |  |
Nominal Amount | $ 137,400 |
Fixed Interest Rate | 2.05% |
Reference Floating Interest Rate | 6-month Euribor |

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- Definition The interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_7&doctype=Standard -URIDate 2018-03-16 + Details
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