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1. OPERATING CONTEXT (Details Narrative) - R$ / shares | Jan. 13, 2020 | Jul. 17, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Apr. 23, 2018 | Dec. 31, 2017
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Disclosure of subsidiaries [line items] |  |  |  |  |  |
Number of shares issued |  |  | 1,258,841,654 | 1,458,752,601 | 199,910,947 | 1,258,841,654
Share price |  |  | R$ 5.00 |  | R$ 5.00 |
Eletrobras [Member] | Events After Reporting Period [Member] |  |  |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |  |  |
Percentage of equity interest in total share capital | 49.00% |  |  |  |  |
Light S.A. ('Light') [Member] |  |  |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |  |  |
Number of shares issued |  | 33,333,333 |  |  |  |
Share price |  | R$ 18.75 |  |  |  |
Description of percentage of equity interest in total share capital |  | With the settlement of the restricted offering, the Company’s equity interest in the total share capital of Light was reduced from 49.99% to 22.58% |  |  |  |
Intial Public Offering [Member] | Light S.A. ('Light') [Member] |  |  |  |  |  |
Disclosure of subsidiaries [line items] |  |  |  |  |  |
Number of shares issued |  | 100,000,000 |  |  |  |

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