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Revenues - Additional Information (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Revenue [abstract] |  |  |
Transmission indemnity revenue | R$ 373 | R$ 751 | R$ 101
Revenue from indemnity by IPCA | 224 |  |
Adjustment of BRR of transmission assets | 149 |  |
Generation indemnity revenue | R$ 271 |  |

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- References No definition available. + Details
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- Definition Adjustment of BRR of Transmission Assets + References No definition available. + Details
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- Definition Revenue from indemnity receivable by extended consumer price index. + References No definition available. + Details
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- Definition Revenue from transmission indemnity. + References No definition available. + Details
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