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Basis of Presentation and Basis of Consolidation (Details) - USD ($) $ in Thousands |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Feb. 15, 2017 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems |  |  |  |
Lease liabilities |  |  | $ 66,471 | $ 82,633
IFRS 16 |  |  |  |
DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems |  |  |  |
Lease liabilities |  |  | 28,250 |
Amount of expected decrease in other operating expenses |  | $ 9,684 |  |
Amount of expected increase in depreciation expense |  | 8,890 |  |
Amount of expected increase in finance costs |  | $ 1,215 |  |
Grupo Villar Mir, S.A.U. |  |  |  |
DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems |  |  |  |
Ownership interest as a percentage | 53.90% |  |  |
Senior Notes due 2022 |  |  |  |
DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems |  |  |  |
Principal amount | $ 350,000 |  | $ 350,000 | $ 350,000
Fixed Interest Rate | 9.375% |  |  |
Redemption price of notes at change of control | 101.00% |  |  |

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