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CONSOLIDATED FINANCIAL STATEMENTS - Associate companies (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Interest in Associate companies |  |  |
Net income (loss) | R$ (338,667) | R$ (2,885,929) | R$ (4,595,986)
Total comprehensive income | (298,366) | (7,773,542) | R$ 1,094,348
Associate companies |  |  |
Interest in Associate companies |  |  |
Net income (loss) | 26,099 | 141,023 |
Total comprehensive income | R$ 26,099 | R$ 141,023 |
Dona Francisca Energtica S.A. |  |  |
Interest in Associate companies |  |  |
Equity interest in associate companies (as a percent) | 51.82% | 51.82% | 51.82%
Corsa Controladora, S.A. de C.V. and subsidiaries |  |  |
Interest in Associate companies |  |  |
Equity interest in associate companies (as a percent) | 49.00% | 49.00% | 49.00%
Corporacin Centro Americana del Acero S.A. and subsidiaries |  |  |
Interest in Associate companies |  |  |
Equity interest in associate companies (as a percent) |  |  | 30.00%

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