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Equity - Distribution of borrowings (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Disclosure of classes of share capital [line items] |  |  |
Non-current gross financial debt | $ 560,738 | $ 458,056 | $ 269,325
Current gross financial debt | 84,651 | 113,281 | 245,262
Gross financial debt | $ 645,389 | $ 571,337 | $ 514,587
Non-current gross financial debt to total gross financial debt (as a percentage) | 86.88% | 80.17% | 52.34%
Current gross financial debt to total gross financial debt (as a percentage) | 13.12% | 19.83% | 47.66%
Gross financial debt (as a percentage) | 100.00% | 100.00% | 100.00%
Gross financial debt, including discontinued operations |  |  | $ 601,546
Spanish energy business classified as held for sale |  |  |
Disclosure of classes of share capital [line items] |  |  |
Non-current gross financial debt |  |  | 76,452
Current gross financial debt |  |  | 10,507
Gross financial debt |  |  | $ 86,959

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