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16. INVESTMENTS (Details 2) - BRL (R$) R$ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | R$ 5,378 |  | R$ 5,235 |  |  |
Gain (loss) by equity method (Income statement) |  | 357 | [1] | 125 |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  | 37 |  | 268 |  |  |
Dividends |  | (399) |  | (284) |  |  |
Additions / acquisitions |  | 119 |  | 33 |  |  |
Other |  | 13 |  | 1 |  |  |
Disposals |  | (120) |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 5,385 |  | 5,378 |  | R$ 5,235 |
Companhia de transmissao centroeste de minas [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) |  |  |  |  |  | 5 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  | (6) |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Light [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance | [2] |  |  |  |  | 1,534 |
Gain (loss) by equity method (Income statement) | [2] |  |  |  |  | 19 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) | [2] |  |  |  |  | (231) |
Dividends | [2] |  |  |  |  | (8) |
Additions / acquisitions | [2] |  |  |  |  |  |
Other | [2] |  |  |  |  | (59) |
Disposals | [2] |  |  |  |  |  |
Reclassification to held for sale | [2] |  |  |  |  | (1,255) |
Ending balance | [2] |  |  |  |  |  |
RME [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance | [2] |  |  |  |  | 383 |
Gain (loss) by equity method (Income statement) | [2] |  |  |  |  | 3 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) | [2] |  |  |  |  | (52) |
Dividends | [2] |  |  |  |  | (1) |
Additions / acquisitions | [2] |  |  |  |  | 104 |
Other | [2] |  |  |  |  | (111) |
Disposals | [2] |  |  |  |  |  |
Reclassification to held for sale | [2] |  |  |  |  | (326) |
Ending balance | [2] |  |  |  |  |  |
Axxiom solucoes tecnologicas [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 13 |  |  | [2] | 12 | [2]
Gain (loss) by equity method (Income statement) |  | (9) | [1],[3] |  |  | (7) | [2]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  | [3] | 4 |  |  | [2]
Dividends |  |  | [3] |  |  |  | [2]
Additions / acquisitions |  |  | [3] | 9 |  |  | [2]
Other |  |  | [3] |  |  | (1) | [2]
Disposals |  |  | [3] |  |  |  | [2]
Reclassification to held for sale | [2] |  |  |  |  | (4) |
Ending balance |  | 4 | [3] | 13 |  |  | [2]
Lightger [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 128 |  |  | [2] | 41 | [2]
Gain (loss) by equity method (Income statement) |  | 10 | [1],[3] |  |  | 3 | [2]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  | [3] | 128 |  | 84 | [2]
Dividends |  | (7) | [3] |  |  | (2) | [2]
Additions / acquisitions |  |  | [3] |  |  |  | [2]
Other |  |  | [3] |  |  |  | [2]
Disposals |  |  | [3] |  |  |  | [2]
Reclassification to held for sale | [2] |  |  |  |  | (126) |
Ending balance |  | 131 | [3] | 128 |  |  | [2]
Guanhaes energia [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 131 |  |  | [2] | 25 | [2]
Gain (loss) by equity method (Income statement) |  |  | [1],[3] |  |  | 30 | [2]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  | [3] | 131 |  |  | [2]
Dividends |  |  | [3] |  |  |  | [2]
Additions / acquisitions |  |  | [3] |  |  | 57 | [2]
Other |  |  | [3] |  |  |  | [2]
Disposals |  |  | [3] |  |  |  | [2]
Reclassification to held for sale | [2] |  |  |  |  | (112) |
Ending balance |  | 131 | [3] | 131 |  |  | [2]
Usina hidreletrica itaocara S.A. [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  | [2] | 4 | [2]
Gain (loss) by equity method (Income statement) |  |  |  | (50) |  | (4) | [2]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  | 5 |  |  | [2]
Dividends |  |  |  |  |  |  | [2]
Additions / acquisitions |  |  |  | 23 |  | 5 | [2]
Other |  |  |  | 22 |  |  | [2]
Disposals | [2] |  |  |  |  |  |
Reclassification to held for sale | [2] |  |  |  |  | (5) |
Ending balance |  |  |  |  |  |  | [2]
Hidreletrica pipoca [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 31 |  | 31 |  | 26 |
Gain (loss) by equity method (Income statement) |  | 11 | [1] | 4 |  | 7 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  | (6) |  | (4) |  | (2) |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 36 |  | 31 |  | 31 |
Madeira energia (santo antonio plant) [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 167 |  | 270 | [4],[5] | 535 | [4],[5]
Gain (loss) by equity method (Income statement) |  | 42 | [1] | (103) |  | (163) | [4],[5]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  | [4],[5]
Dividends |  |  |  |  |  |  | [4],[5]
Additions / acquisitions |  |  |  |  |  | 25 | [4],[5]
Other |  |  |  |  |  | (127) | [4],[5]
Disposals |  |  |  |  |  |  | [4],[5]
Reclassification to held for sale | [4],[5] |  |  |  |  |  |
Ending balance |  | 209 |  | 167 |  | 270 | [4],[5]
FIP melbourne (usina de santo antonio) [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 385 |  | 470 | [5] | 582 | [5]
Gain (loss) by equity method (Income statement) |  |  |  | (85) |  | (139) | [5]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  | [5]
Dividends |  |  |  |  |  |  | [5]
Additions / acquisitions |  |  |  |  |  | 27 | [5]
Other |  |  |  |  |  |  | [5]
Disposals | [5] |  |  |  |  |  |
Reclassification to held for sale | [5] |  |  |  |  |  |
Ending balance |  |  |  | 385 |  | 470 | [5]
Hidreletrica cachoeirao [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 54 |  | 49 |  | 58 |
Gain (loss) by equity method (Income statement) |  | 9 | [1] | 11 |  | 10 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  | (10) |  | (6) |  | (19) |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 53 |  | 54 |  | 49 |
Baguari energia [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 157 |  | 162 |  | 148 |
Gain (loss) by equity method (Income statement) |  | 23 | [1] | 22 |  | 28 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  | (21) |  | (27) |  | (15) |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  | 1 |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 159 |  | 157 |  | 162 |
Central eolica praias de parajuru [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance | [6] |  |  |  |  | 60 |
Gain (loss) by equity method (Income statement) | [6] |  |  |  |  | (6) |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) | [6] |  |  |  |  | 21 |
Dividends | [6] |  |  |  |  |  |
Additions / acquisitions | [6] |  |  |  |  | 74 |
Other | [6] |  |  |  |  | (146) |
Disposals | [6] |  |  |  |  | (3) |
Reclassification to held for sale | [6] |  |  |  |  |  |
Ending balance | [6] |  |  |  |  |  |
Central eolica volta do rio [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance | [6] |  |  |  |  | 68 |
Gain (loss) by equity method (Income statement) | [6] |  |  |  |  | (16) |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) | [6] |  |  |  |  | 59 |
Dividends | [6] |  |  |  |  |  |
Additions / acquisitions | [6] |  |  |  |  | 92 |
Other | [6] |  |  |  |  | (181) |
Disposals | [6] |  |  |  |  | (22) |
Reclassification to held for sale | [6] |  |  |  |  |  |
Ending balance | [6] |  |  |  |  |  |
Central eolica praias de morgado [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance | [6] |  |  |  |  | 51 |
Gain (loss) by equity method (Income statement) | [6] |  |  |  |  | (15) |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) | [6] |  |  |  |  |  |
Dividends | [6] |  |  |  |  |  |
Additions / acquisitions | [6] |  |  |  |  |  |
Other | [6] |  |  |  |  | (24) |
Disposals | [6] |  |  |  |  | (12) |
Reclassification to held for sale | [6] |  |  |  |  |  |
Ending balance | [6] |  |  |  |  |  |
Amazonia energia (belo monte plant) [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 1,028 |  | 1,013 |  | 867 |
Gain (loss) by equity method (Income statement) |  | (63) | [1] | 15 |  | 80 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  |  |  |  |  | 69 |
Other |  |  |  |  |  | (3) |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 965 |  | 1,028 |  | 1,013 |
Alianca norte (belo monte plant) [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 671 |  | 664 |  | 577 |
Gain (loss) by equity method (Income statement) |  | (40) | [1] | 6 |  | 44 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  |  |  | 1 |  | 43 |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 631 |  | 671 |  | 664 |
Ativas data center [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 16 |  | 16 |  | 17 |
Gain (loss) by equity method (Income statement) |  | 1 | [1] |  |  | (1) |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 17 |  | 16 |  | 16 |
TAESA [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 1,213 |  | 1,143 | [2] | 1,101 | [2]
Gain (loss) by equity method (Income statement) |  | 494 | [1] | 210 |  | 225 | [2]
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  | [2]
Dividends |  | (240) |  | (141) |  | (208) | [2]
Additions / acquisitions |  |  |  |  |  |  | [2]
Other |  |  |  | 1 |  | 25 | [2]
Disposals |  |  |  |  |  |  | [2]
Reclassification to held for sale | [2] |  |  |  |  |  |
Ending balance |  | 1,467 |  | 1,213 |  | 1,143 | [2]
Renova [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  | 282 |
Gain (loss) by equity method (Income statement) |  |  |  |  |  | (282) |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  |  |  |  |  |  |
Alianca geracao [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 1,192 |  | 1,217 |  | 1,242 |
Gain (loss) by equity method (Income statement) |  | 89 | [1] | 78 |  | 65 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  | (114) |  | (103) |  | (90) |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 1,167 |  | 1,192 |  | 1,217 |
Retiro baixo [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 180 |  | 171 |  | 158 |
Gain (loss) by equity method (Income statement) |  | 15 | [1] | 12 |  | 10 |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  | (3) |  | (3) |
Additions / acquisitions |  |  |  |  |  | 6 |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 195 |  | 180 |  | 171 |
UFV janauba geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 10 |  | 9 |  |  |
Gain (loss) by equity method (Income statement) |  | 1 | [1] | 1 |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  | (1) |  |  |  |  |
Additions / acquisitions |  |  |  |  |  | 9 |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Reclassification to held for sale |  |  |  |  |  |  |
Ending balance |  | 10 |  | 10 |  | 9 |
Total of investments [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 5,400 |  | 5,235 |  | 7,792 |
Gain (loss) by equity method (Income statement) |  | 366 | [1] | 125 |  | (104) |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  | 37 |  | 268 |  | (119) |
Dividends |  | (399) |  | (284) |  | (354) |
Additions / acquisitions |  | 118 |  | 33 |  | 511 |
Other |  | 13 |  | 23 |  | (626) |
Disposals |  | (120) |  |  |  | (37) |
Reclassification to held for sale |  |  |  |  |  | (1,828) |
Ending balance |  | 5,415 |  | 5,400 |  | 5,235 |
Companhia de transmissao centroeste de minas [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 24 |  | 20 |  | 21 |
Gain (loss) by equity method (Income statement) |  |  | [1] | 4 |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  | 37 |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 45 |  |  |  |  |
Other |  | 14 |  |  |  |  |
Disposals |  | (120) |  |  |  |  |
Ending balance |  |  |  | 24 |  | 20 |
Itaocara - equity deficit [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | (22) |  |  | [7] |  |
Gain (loss) by equity method (Income statement) |  | (9) | [1],[7] |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  | [7] |  |  |  |
Dividends |  |  | [7] |  |  |  |
Additions / acquisitions |  | 1 | [7] |  |  |  |
Other |  |  | [7] | (22) |  |  |
Disposals | [7] |  |  |  |  |  |
Ending balance |  | (30) | [7] | (22) |  |  | [7]
FIP Melbourne (Santo Antonio plant) [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  | 385 |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | (227) |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  |  |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 158 |  | 385 |  |  |
UFV Corinto Geracao de Energia Eletrica Distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | 1 |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 9 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 10 |  |  |  |  |
UFV Manga Geracao de Energia Eletrica Distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | 1 |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 10 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 11 |  |  |  |  |
UFV Bonfinopolis II Geracao de Energia Eletrica Distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] |  |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 6 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 6 |  |  |  |  |
UFV lagoa grande geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | 3 |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 12 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 15 |  |  |  |  |
UFV lontra geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | 3 |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 14 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 17 |  |  |  |  |
UFV mato verde geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | 1 |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 5 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 6 |  |  |  |  |
UFV mirabela geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] |  |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 5 |  |  |  |  |
Other |  | (1) |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 4 |  |  |  |  |
UFV porteirinha i geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] |  |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 6 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | 6 |  |  |  |  |
UFV porteirinha ii geracao de energia eletrica distribuida [member] |  |  |  |  |  |  |
Disclosure of detailed information about investment property [line items] |  |  |  |  |  |  |
Beginning balance |  |  |  |  |  |  |
Gain (loss) by equity method (Income statement) | [1] | 1 |  |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired (step- acquisition) |  |  |  |  |  |  |
Dividends |  |  |  |  |  |  |
Additions / acquisitions |  | 6 |  |  |  |  |
Other |  |  |  |  |  |  |
Disposals |  |  |  |  |  |  |
Ending balance |  | R$ 7 |  |  |  |  |
[1] | Includes bargain purchase related to the acquisition of the joint-controlled entities UFV Corinto, UFV Manga, UFV Lagoa Grande, UFV Lontra, UFV Mato Verde and UFV Porteirinha II, in the amount of R$7.
[2] | Others arises from first adoption of the new accounting standards on January 1, 2018, recognized by the investees directly in equity without inclusion in the Income statement. The column Reclassification to held for sale includes the effect of the reclassification of the investment in Light, Axxion, Lightger, Guanhaes and Itaocara to Non-current assets held for sale, in accordance with IFRS 5.
[3] | With the loss of control of Light, the remaining equity interest in these investees was recognized as an investment in affiliates or jointly-controlled subsidiaries, and measured by the equity method, in accordance with IFRS 10. More details see notes 1 and 33.
[4] | Due to the result of analysis of impairment indication, due to the recurring losses incurred by Madeira, a provision was recognized for loss of part of the residual added value of the investment in Madeira, to limit its balance to the minimum value of the excess of future economic benefits arising from use of the net fixed asset on December, 31, 2018, using the nominal WACC of 9.59% as the discount rate. The provision is presented in the statement of income for the year ended December 31, 2018 as Impairment loss on Investments.
[5] | In October 2018 the Company subscribed capital increases in Mesa and FIP Melbourne, of R$25 and R$26, respectively. These funds were entirely applied in capital contributions to Santo Antonio Energia S.A. ('Saesa' or 'Santo Antonio Hydroelectric Plant').
[6] | Arising from the business combination between the Company and Energimp. The rights to exploitation of the regulated activity are classified in the consolidated statement of financial position under Intangible.
[7] | On December 31, 2019, the investee had negative shareholders' equity. Thus, after reducing the accounting value of its interest to zero, the Company recognized the provision for losses on investments, in the amount of R$22, resulting from contractual obligations assumed with the subsidiary and the other shareholders.

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