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34. ASSETS AS HELD FOR SALE AND DISCONTINUED OPERATIONS (Details 1) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | R$ (1,850) |  |
Proceeds from disposal of equity interest | 625 |  |
Remeasurement at fair value of remaining equity interest | 1,525 |  |
Others | 9 |  |
Effects on the income statement, before taxes | 309 |  |
Income tax and social contribution tax | (85) |  |
Net income after tax for the year from discontinued operations | 224 | R$ 363 |
Light [Member] |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | (1,060) |  |
Remeasurement at fair value of remaining equity interest | 1,258 |  |
Effects on the income statement, before taxes | 198 |  |
Income tax and social contribution tax | (47) |  |
Net income after tax for the year from discontinued operations | 151 |  |
Lightger [Member] |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | (126) |  |
Remeasurement at fair value of remaining equity interest | 128 |  |
Effects on the income statement, before taxes | 2 |  |
Income tax and social contribution tax |  |  |
Net income after tax for the year from discontinued operations | 2 |  |
Guanhaes [Member] |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | (141) |  |
Remeasurement at fair value of remaining equity interest | 131 |  |
Others | 4 |  |
Effects on the income statement, before taxes | (6) |  |
Income tax and social contribution tax |  |  |
Net income after tax for the year from discontinued operations | (6) |  |
Axxion [Member] |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | (4) |  |
Remeasurement at fair value of remaining equity interest | 4 |  |
Others | 5 |  |
Effects on the income statement, before taxes | 5 |  |
Income tax and social contribution tax |  |  |
Net income after tax for the year from discontinued operations | 5 |  |
Itaocara [Member] |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | (4) |  |
Remeasurement at fair value of remaining equity interest | 4 |  |
Effects on the income statement, before taxes |  |  |
Income tax and social contribution tax |  |  |
Net income after tax for the year from discontinued operations |  |  |
Profit Loss on Disposal Of Equity Interest [Member] | Light [Member] |  |  |
Disclosure of assets and liabilities classified as held for sale [line items] |  |  |
Prior equity interest - Assets held for sale | (515) |  |
Proceeds from disposal of equity interest | 625 |  |
Effects on the income statement, before taxes | 110 |  |
Income tax and social contribution tax | (38) |  |
Net income after tax for the year from discontinued operations | R$ 72 |  |

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