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Income and expenses - Sale by Segment (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Sales by segment |  |  |  |  |
Sales | $ 2,274,038 | $ 1,741,693 | [1] | $ 1,576,037 | [1]
Eliminations |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | (187,305) | (65,353) |  | (127,199) |
Electrometallurgy - North America |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 710,716 | 541,143 |  | 521,192 |
Electrometallurgy - North America | Operating segments |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 710,716 | 541,143 |  | 521,192 |
Electrometallurgy - Europe |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 1,447,973 | 1,083,200 |  | 949,547 |
Electrometallurgy - Europe | Operating segments |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 1,447,973 | 1,083,200 |  | 949,547 |
Electrometallurgy - South Africa |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 208,543 | 122,504 |  | 142,160 |
Electrometallurgy - South Africa | Operating segments |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 208,543 | 122,504 |  | 142,160 |
Other segments |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | 94,111 | 60,199 |  | 90,337 |
Other segments | Operating segments |  |  |  |  |
Sales by segment |  |  |  |  |
Sales | $ 94,111 | $ 60,199 |  | $ 90,337 |
[1] | The amounts for 2016 have been re-presented to show the results of the Spanish energy business within profit (loss) from continuing operations, as described in Note 1 to the consolidated financial statements.

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