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18. INVESTMENTS (Details 5) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Amazonia [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 74.50% |  | 74.50% |
Indirect stake | 5.76% |  | 12.46% |
Renova [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 36.23% | [1] | 36.23% | [2]
Indirect stake |  | [1] | 8.39% | [2]
Lightger [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 49.00% |  | 49.00% |
Indirect stake | 11.52% |  | 24.92% |
Guanhaes [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 49.00% |  | 49.00% |
Indirect stake | 11.52% |  | 24.92% |
Axxion [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 49.00% |  | 49.00% |
Indirect stake | 11.52% |  | 24.92% |
UHE Itaocara [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 49.00% |  | 49.00% |
Indirect stake | 11.52% |  | 24.92% |
Light [Member] |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |
Direct stake | 22.58% |  | 26.06% |
Indirect stake |  |  | 22.80% |
[1] | On October 15, 2019, Light sold the totality of its shares in the jointly-controlled entity Renova to CG I Fundo de Investimento em Participacoes. Further details as follows.
[2] | Bank Financial Notes (Letras Financeiras, or LFs) are fixed- rate fixed-income securities, issued by banks and that accrued interest a percentage of the CDI rate published by Cetip. The LFs had remuneration rates varying between 101.95% and 113% of the CDI rate in 2019 (102% and 111.25% in 2018 and 102.01% to 112% in 2017).

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