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34. ASSETS AS HELD FOR SALE AND DISCONTINUED OPERATIONS (Details Narrative) - BRL (R$) R$ / shares in Units, R$ in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Jul. 17, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Apr. 23, 2018
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |  |  |
Number of shares sold (in shares) |  | 1,258,841,654 | 1,458,752,601 | 1,258,841,654 | 199,910,947
Share price |  | R$ 5.00 |  |  | R$ 5.00
Gain on disposal of assets |  | R$ 998 | R$ 893 |  |
Capital gain on assets |  | 72 |  |  |
Estimated costs for the sale |  | 29 |  |  |
Dividends declared |  | 364 |  |  |
Disposal of control |  | 224 |  |  |
Light [Member] |  |  |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |  |  |
Dividends declared |  | R$ 73 |  |  |
Bottom Of Range [Member] |  |  |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |  |  |
Voting rights percentage |  | 22.58% |  |  |
Top of Range [Member] |  |  |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |  |  |
Voting rights percentage |  | 49.99% |  |  |
Initial Public Offering [Member] |  |  |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |  |  |
Number of shares sold (in shares) | 33,333,333 |  |  |  |
Proceeds from issuance of shares | R$ 625 |  |  |  |
Share price | R$ 18.75 |  |  |  |

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