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5. OPERATING SEGMENTS (Details) - BRL (R$) R$ in Millions |  | 12 Months Ended
--- | --- | ---
Apr. 30, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | R$ 54,083 | R$ 50,527 |  | R$ 60,339 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  | 5,415 | 5,399 |  | 5,235 |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  | 1,258 | 1,258 |  |  |
ADDITIONS TO THE SEGMENT |  |  | 1,918 | 2,201 |  | 1,632 |
NET REVENUE |  |  | 25,228 | 25,487 | [1] | 22,266 |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  | (12,111) | (11,286) | [1] | (11,084) |
Charges for use of the national grid |  |  | (1,748) | (1,426) | [1] | (1,480) |
Gas bought for resale |  |  | (1,083) | (1,436) |  | (1,238) |
Operating costs, total |  |  | (14,942) | (14,148) |  | (13,802) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  | (1,276) | (1,272) |  | (1,410) |
Employees' and managers' profit sharing |  |  | (142) | (263) |  | (77) |
Post-employment obligations |  |  | (438) | (408) |  | (337) |
Materials |  |  | (79) | (91) |  | (104) |
Raw materials and inputs for production of energy |  |  |  |  |  |  |
Outsourced services |  |  | (1,265) | (1,239) |  | (1,087) |
Depreciation and amortization |  |  | (989) | (958) |  | (835) |
Operating provisions (reversals) |  |  | (423) | (2,401) |  | (466) |
Construction costs |  |  | (1,581) | (1,200) |  | (897) |
Other operating expenses, net |  |  | (297) | (495) |  | (405) |
Total cost of operation |  |  | (6,490) | (8,327) |  | (5,618) |
OPERATING COSTS AND EXPENSES |  |  | (21,432) | (22,475) |  | (19,420) |
Equity in earnings of unconsolidated investees, net |  |  | 357 | 125 | [1] | (104) |
Dividends declared by investee classified as held for sale |  |  |  | 73 |  |  |
Gain on a bargain purchase and remeasurement of previously held equity interest in subsidiary acquired in business combinations transactions |  |  | 51 |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired |  |  |  |  |  | (119) |
Impairment for investments |  |  |  |  |  | (127) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  | 4,706 | 3,210 | [1] | 2,529 |
Finance income |  |  | 2,445 | 3,207 | [1] | 1,706 |
Finance expenses |  |  | (3,350) | (1,847) | [1] | (2,224) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  | 3,801 | 4,469 | [1] | 2,011 |
Income tax and social contribution tax |  |  | (936) | (1,599) |  | (610) |
Net income for the year from continuing operations |  |  | 2,865 | 2,969 | [1] | 1,401 | [1]
DISCONTINUED OPERATIONS |  |  |  |  |  |  |
NET INCOME AFTER TAX FROM DISCONTINUED OPERATIONS |  |  |  | 224 | [1] | 363 | [1]
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
Equity gain (loss) on Other comprehensive income in subsidiary and jointly-controlled entity, net of tax |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  | 3,193 |  |  |
NET INCOME FOR THE YEAR |  | R$ 2,864 | 2,865 | 3,194 | [1] | 1,764 | [1]
Equity holders of the parent |  |  | 2,864 | 3,193 |  | 1,722 |
Non-controlling interests |  |  | 1 | 1 | [1] | 42 |
Operating Segments [member] | Elimination Segments [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | (663) | (1,127) |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  |  |  |  |  |
NET REVENUE |  |  | (333) | (307) |  |  |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  | 76 | 72 |  |  |
Charges for use of the national grid |  |  |  | 223 |  |  |
Gas bought for resale |  |  |  |  |  |  |
Operating costs, total |  |  | 326 | 295 |  |  |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  |  |  |  |  |
Employees' and managers' profit sharing |  |  |  |  |  |  |
Post-employment obligations |  |  |  |  |  |  |
Materials |  |  |  |  |  |  |
Outsourced services |  |  | 7 | 7 |  |  |
Depreciation and amortization |  |  |  |  |  |  |
Operating provisions (reversals) |  |  |  |  |  |  |
Construction costs |  |  |  |  |  |  |
Other operating expenses, net |  |  |  | 5 |  |  |
Total cost of operation |  |  | 8 | 12 |  |  |
OPERATING COSTS AND EXPENSES |  |  | 333 | (307) |  |  |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  |  |
Operating Segments [member] | Restated [member] | Elimination Segments [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | (957) |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
NET REVENUE |  |  |  |  |  | (293) |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  |  |  |  | 71 |
Charges for use of the national grid |  |  |  |  |  | 199 |
Operating costs, total |  |  |  |  |  | 270 |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Outsourced services |  |  |  |  |  | 15 |
Other operating expenses, net |  |  |  |  |  | 8 |
Total cost of operation |  |  |  |  |  | 23 |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | 293 |
Operating Segments [member] | Other Segments [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | 3,712 | 3,888 |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  | 21 | 29 |  |  |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  |  | 9 |  |  |
NET REVENUE |  |  | 105 | 324 |  |  |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  |  |  |  |  |
Charges for use of the national grid |  |  |  |  |  |  |
Gas bought for resale |  |  |  |  |  |  |
Operating costs, total |  |  |  |  |  |  |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  | (24) | (35) |  |  |
Employees' and managers' profit sharing |  |  | (14) | (17) |  |  |
Post-employment obligations |  |  | (47) | (43) |  |  |
Materials |  |  |  | (3) |  |  |
Raw materials and inputs for production of energy |  |  | (33) |  |  |  |
Outsourced services |  |  | (3) | (40) |  |  |
Depreciation and amortization |  |  | (18) | (4) |  |  |
Operating provisions (reversals) |  |  |  | (188) |  |  |
Construction costs |  |  |  |  |  |  |
Other operating expenses, net |  |  | (16) |  |  |  |
Total cost of operation |  |  | (155) | (330) |  |  |
OPERATING COSTS AND EXPENSES |  |  | (155) | (330) |  |  |
Equity in earnings of unconsolidated investees, net |  |  | (8) | (2) |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  | (58) | (8) |  |  |
Finance income |  |  |  | 269 |  |  |
Finance expenses |  |  | (4) | (19) |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  | (62) | 242 |  |  |
Income tax and social contribution tax |  |  | (6) | (124) |  |  |
Net income for the year from continuing operations |  |  | (68) | 118 |  |  |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  | 118 |  |  |
NET INCOME FOR THE YEAR |  |  | (68) | 118 |  |  |
Equity holders of the parent |  |  | (68) | 118 |  |  |
Operating Segments [member] | Other Segments [member] | Restated [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | 2,607 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  | 17 |
NET REVENUE |  |  |  |  |  | 134 |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  |  |  |  | (29) |
Employees' and managers' profit sharing |  |  |  |  |  | (9) |
Post-employment obligations |  |  |  |  |  | (40) |
Outsourced services |  |  |  |  |  | (30) |
Depreciation and amortization |  |  |  |  |  | (1) |
Operating provisions (reversals) |  |  |  |  |  | (18) |
Other operating expenses, net |  |  |  |  |  | (112) |
Total cost of operation |  |  |  |  |  | (239) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | (239) |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  | (14) |
Remeasurement of previously held equity interest in subsidiaries acquired |  |  |  |  |  | (147) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |  |  |  | (266) |
Finance income |  |  |  |  |  | 13 |
Finance expenses |  |  |  |  |  | (19) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |  |  |  | (272) |
Income tax and social contribution tax |  |  |  |  |  | 57 |
Net income for the year from continuing operations |  |  |  |  |  | (215) |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  |  |  | (115) |
NET INCOME FOR THE YEAR |  |  |  |  |  | (215) |
Equity holders of the parent |  |  |  |  |  | (217) |
Non-controlling interests |  |  |  |  |  | 2 |
Operating Segments [member] | Gas Segment [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | 2,615 | 2,689 |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  | 50 | 934 |  |  |
NET REVENUE |  |  | 1,664 | 1,858 |  |  |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  |  |  |  |  |
Charges for use of the national grid |  |  |  |  |  |  |
Gas bought for resale |  |  | (1,083) | (1,436) |  |  |
Operating costs, total |  |  | (1,083) | (1,436) |  |  |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  | (60) | (46) |  |  |
Employees' and managers' profit sharing |  |  |  |  |  |  |
Post-employment obligations |  |  |  |  |  |  |
Materials |  |  | (1) | (20) |  |  |
Outsourced services |  |  | (25) | (2) |  |  |
Depreciation and amortization |  |  | (106) | (86) |  |  |
Operating provisions (reversals) |  |  | (1) | (2) |  |  |
Construction costs |  |  | (50) | (43) |  |  |
Other operating expenses, net |  |  | (12) | (10) |  |  |
Total cost of operation |  |  | (255) | (209) |  |  |
OPERATING COSTS AND EXPENSES |  |  | (1,338) | (1,645) |  |  |
OPERATING INCOME BEFORE EQUITY GAINS (LOSSES) AND FINANCE INCOME (EXPENSES) |  |  |  | 213 |  |  |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  | 326 |  |  |  |
Finance income |  |  | 44 | 21 |  |  |
Finance expenses |  |  | (58) | (46) |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  | 312 | 188 |  |  |
Income tax and social contribution tax |  |  | (58) | (48) |  |  |
Net income for the year from continuing operations |  |  | 227 | 140 |  |  |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
Equity gain (loss) on Other comprehensive income in subsidiary and jointly-controlled entity, net of tax |  |  |  | 139 |  |  |
NET INCOME FOR THE YEAR |  |  | 227 | 140 |  |  |
Equity holders of the parent |  |  | 226 | 139 |  |  |
Non-controlling interests |  |  |  | 1 |  |  |
Operating Segments [member] | Gas Segment [member] | Restated [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | 1,822 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  |  |  |  | 70 |
NET REVENUE |  |  |  |  |  | 1,619 |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Gas bought for resale |  |  |  |  |  | (1,238) |
Operating costs, total |  |  |  |  |  | (1,238) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  |  |  |  | (60) |
Materials |  |  |  |  |  | (2) |
Outsourced services |  |  |  |  |  | (20) |
Depreciation and amortization |  |  |  |  |  | (74) |
Operating provisions (reversals) |  |  |  |  |  | 2 |
Construction costs |  |  |  |  |  | (44) |
Other operating expenses, net |  |  |  |  |  | (13) |
Total cost of operation |  |  |  |  |  | (211) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | (1,449) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |  |  |  | 170 |
Finance income |  |  |  |  |  | 84 |
Finance expenses |  |  |  |  |  | (38) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |  |  |  | 216 |
Income tax and social contribution tax |  |  |  |  |  | (53) |
Net income for the year from continuing operations |  |  |  |  |  | 163 |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME FOR THE YEAR |  |  |  |  |  | 163 |
Equity holders of the parent |  |  |  |  |  | 162 |
Non-controlling interests |  |  |  |  |  | 1 |
Operating Segments [member] | Energy Distribution Segment [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | 26,399 | 25,616 |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  | 1,258 | 1,258 |  |  |
ADDITIONS TO THE SEGMENT |  |  | 1,384 | 936 |  |  |
NET REVENUE |  |  | 16,512 | 15,919 |  |  |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  | (8,161) | (7,517) |  |  |
Charges for use of the national grid |  |  | (1,799) | (1,459) |  |  |
Gas bought for resale |  |  |  |  |  |  |
Operating costs, total |  |  | (9,960) | (8,976) |  |  |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  | (886) | (869) |  |  |
Employees' and managers' profit sharing |  |  | (92) | (183) |  |  |
Post-employment obligations |  |  | (297) | (277) |  |  |
Materials |  |  | (61) | (63) |  |  |
Outsourced services |  |  | (1,055) | (1,016) |  |  |
Depreciation and amortization |  |  | (668) | (652) |  |  |
Operating provisions (reversals) |  |  | (272) | (1,101) |  |  |
Construction costs |  |  | (1,384) | (937) |  |  |
Other operating expenses, net |  |  | (212) | (299) |  |  |
Total cost of operation |  |  | (4,927) | (5,397) |  |  |
OPERATING COSTS AND EXPENSES |  |  | (14,887) | (14,373) |  |  |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  |  |
Dividends declared by investee classified as held for sale |  |  |  | 73 |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  | 1,625 | 1,619 |  |  |
Finance income |  |  | 514 | 1,535 |  |  |
Finance expenses |  |  | (505) | (632) |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  | 1,634 | 2,522 |  |  |
Income tax and social contribution tax |  |  | (430) | (806) |  |  |
Net income for the year from continuing operations |  |  | 1,204 | 1,716 |  |  |
DISCONTINUED OPERATIONS |  |  |  |  |  |  |
NET INCOME AFTER TAX FROM DISCONTINUED OPERATIONS |  |  |  | 224 |  |  |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  | 1,940 |  |  |
NET INCOME FOR THE YEAR |  |  | 1,204 | 1,940 |  |  |
Equity holders of the parent |  |  | 1,204 | 1,940 |  |  |
Operating Segments [member] | Energy Distribution Segment [member] | Restated [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | 37,840 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  |  |  |  | 856 |
NET REVENUE |  |  |  |  |  | 13,757 |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  |  |  |  | (7,238) |
Charges for use of the national grid |  |  |  |  |  | (1,463) |
Operating costs, total |  |  |  |  |  | (8,701) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  |  |  |  | (965) |
Employees' and managers' profit sharing |  |  |  |  |  | (51) |
Post-employment obligations |  |  |  |  |  | (224) |
Materials |  |  |  |  |  | (58) |
Outsourced services |  |  |  |  |  | (880) |
Depreciation and amortization |  |  |  |  |  | (595) |
Operating provisions (reversals) |  |  |  |  |  | (332) |
Construction costs |  |  |  |  |  | (757) |
Other operating expenses, net |  |  |  |  |  | (203) |
Total cost of operation |  |  |  |  |  | (4,065) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | (12,766) |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  | 33 |
Remeasurement of previously held equity interest in subsidiaries acquired |  |  |  |  |  | (52) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |  |  |  | 972 |
Finance income |  |  |  |  |  | 434 |
Finance expenses |  |  |  |  |  | (621) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |  |  |  | 785 |
Income tax and social contribution tax |  |  |  |  |  | (217) |
Net income for the year from continuing operations |  |  |  |  |  | 568 |
DISCONTINUED OPERATIONS |  |  |  |  |  |  |
NET INCOME AFTER TAX FROM DISCONTINUED OPERATIONS |  |  |  |  |  | 62 |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  |  |  | 630 |
NET INCOME FOR THE YEAR |  |  |  |  |  | 630 |
Equity holders of the parent |  |  |  |  |  | 599 |
Non-controlling interests |  |  |  |  |  | 31 |
Operating Segments [member] | Energy Generation Segment [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | 16,150 | 14,749 |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  | 3,927 | 4,133 |  |  |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  | 238 | 102 |  |  |
NET REVENUE |  |  | 6,537 | 6,882 |  |  |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  | (4,026) | (3,841) |  |  |
Charges for use of the national grid |  |  | (199) | (190) |  |  |
Gas bought for resale |  |  |  |  |  |  |
Operating costs, total |  |  | (4,225) | (4,031) |  |  |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  | (192) | (207) |  |  |
Employees' and managers' profit sharing |  |  | (24) | (36) |  |  |
Post-employment obligations |  |  | (53) | (50) |  |  |
Materials |  |  | (13) | (17) |  |  |
Outsourced services |  |  | (113) | (125) |  |  |
Depreciation and amortization |  |  | (207) | (210) |  |  |
Operating provisions (reversals) |  |  | (122) | (975) |  |  |
Construction costs |  |  |  |  |  |  |
Other operating expenses, net |  |  | (68) | (175) |  |  |
Total cost of operation |  |  | (792) | (1,795) |  |  |
OPERATING COSTS AND EXPENSES |  |  | (5,017) | (5,826) |  |  |
OPERATING INCOME BEFORE EQUITY GAINS (LOSSES) AND FINANCE INCOME (EXPENSES) |  |  | (129) |  |  |  |
Equity in earnings of unconsolidated investees, net |  |  |  | (88) |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  | 1,391 | 968 |  |  |
Finance income |  |  | 1,711 | 1,282 |  |  |
Finance expenses |  |  | (2,509) | (1,035) |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  | 593 | 1,215 |  |  |
Income tax and social contribution tax |  |  | (206) | (551) |  |  |
Net income for the year from continuing operations |  |  | 387 | 664 |  |  |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  | 664 |  |  |
NET INCOME FOR THE YEAR |  |  | 387 | 664 |  |  |
Equity holders of the parent |  |  | 387 | 664 |  |  |
Operating Segments [member] | Energy Generation Segment [member] | Restated [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | 14,671 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  | 4,055 |
ADDITIONS TO THE SEGMENT |  |  |  |  |  | 559 |
NET REVENUE |  |  |  |  |  | 6,374 |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  |  |  |  | (3,917) |
Charges for use of the national grid |  |  |  |  |  | (216) |
Operating costs, total |  |  |  |  |  | (4,133) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  |  |  |  | (230) |
Employees' and managers' profit sharing |  |  |  |  |  | (10) |
Post-employment obligations |  |  |  |  |  | (46) |
Materials |  |  |  |  |  | (39) |
Outsourced services |  |  |  |  |  | (123) |
Depreciation and amortization |  |  |  |  |  | (164) |
Operating provisions (reversals) |  |  |  |  |  | (107) |
Other operating expenses, net |  |  |  |  |  | (65) |
Total cost of operation |  |  |  |  |  | (784) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | (4,917) |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  | (353) |
Remeasurement of previously held equity interest in subsidiaries acquired |  |  |  |  |  | 80 |
Impairment for investments |  |  |  |  |  | (127) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |  |  |  | 1,057 |
Finance income |  |  |  |  |  | 1,113 |
Finance expenses |  |  |  |  |  | (1,536) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |  |  |  | 634 |
Income tax and social contribution tax |  |  |  |  |  | (276) |
Net income for the year from continuing operations |  |  |  |  |  | 358 |
DISCONTINUED OPERATIONS |  |  |  |  |  |  |
NET INCOME AFTER TAX FROM DISCONTINUED OPERATIONS |  |  |  |  |  | 11 |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME FOR THE YEAR |  |  |  |  |  | 369 |
Equity holders of the parent |  |  |  |  |  | 361 |
Non-controlling interests |  |  |  |  |  | 8 |
Operating Segments [member] | Telecommunications segment [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
Operating Segments [member] | Telecommunications segment [member] | Restated [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | 10 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT | [2] |  |  |  |  | 9 |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel | [2] |  |  |  |  | (18) |
Materials | [2] |  |  |  |  | (1) |
Outsourced services | [2] |  |  |  |  | (9) |
Depreciation and amortization | [2] |  |  |  |  | (1) |
Operating provisions (reversals) | [2] |  |  |  |  | 1 |
Other operating expenses, net | [2] |  |  |  |  | (3) |
Total cost of operation | [2] |  |  |  |  | (31) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | (31) |
Equity in earnings of unconsolidated investees, net | [2] |  |  |  |  | (1) |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) | [2] |  |  |  |  | (32) |
Finance income | [2] |  |  |  |  | 1 |
Finance expenses | [2] |  |  |  |  | (5) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX | [2] |  |  |  |  | (36) |
Income tax and social contribution tax | [2] |  |  |  |  | 12 |
Net income for the year from continuing operations | [2] |  |  |  |  | (24) |
DISCONTINUED OPERATIONS |  |  |  |  |  |  |
NET INCOME AFTER TAX FROM DISCONTINUED OPERATIONS | [2] |  |  |  |  | 290 |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  |  |  | 266 |
NET INCOME FOR THE YEAR | [2] |  |  |  |  | 266 |
Equity holders of the parent | [2] |  |  |  |  | 266 |
Operating Segments [member] | Energy Transmission Segment [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  | 5,870 | 4,712 |  |  |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  | 1,467 | 1,237 |  |  |
INVESTMENTS IN AFFILIATES CLASSIFIED AS HELD FOR SALE |  |  |  |  |  |  |
ADDITIONS TO THE SEGMENT |  |  | 246 | 220 |  |  |
NET REVENUE |  |  | 743 | 811 |  |  |
COST OF ENERGY AND GAS |  |  |  |  |  |  |
Energy bought for resale |  |  |  |  |  |  |
Charges for use of the national grid |  |  |  |  |  |  |
Gas bought for resale |  |  |  |  |  |  |
Operating costs, total |  |  |  |  |  |  |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  | (114) | (115) |  |  |
Employees' and managers' profit sharing |  |  | (12) | (27) |  |  |
Post-employment obligations |  |  | (41) | (38) |  |  |
Materials |  |  | (4) | (6) |  |  |
Outsourced services |  |  | (46) | (45) |  |  |
Depreciation and amortization |  |  | (5) | (6) |  |  |
Operating provisions (reversals) |  |  | (10) | (135) |  |  |
Construction costs |  |  | (147) | (220) |  |  |
Other operating expenses, net |  |  | 11 | (16) |  |  |
Total cost of operation |  |  | (368) | (608) |  |  |
OPERATING COSTS AND EXPENSES |  |  | (368) | (608) |  |  |
Equity in earnings of unconsolidated investees, net |  |  | 494 | 215 |  |  |
Dividends declared by investee classified as held for sale |  |  | 502 |  |  |  |
Remeasurement of previously held equity interest in subsidiaries acquired |  |  | 52 |  |  |  |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  | 1,422 | 418 |  |  |
Finance income |  |  | 175 | 98 |  |  |
Finance expenses |  |  | (274) | (115) |  |  |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  | 1,323 | 401 |  |  |
Income tax and social contribution tax |  |  | (209) | (70) |  |  |
Net income for the year from continuing operations |  |  | 1,114 | 331 |  |  |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  | 331 |  |  |
NET INCOME FOR THE YEAR |  |  | 1,114 | 331 |  |  |
Equity holders of the parent |  |  | R$ 1,114 | R$ 331 |  |  |
Operating Segments [member] | Energy Transmission Segment [member] | Restated [member] |  |  |  |  |  |  |
Disclosure of operating segments [line items] |  |  |  |  |  |  |
SEGMENT ASSETS |  |  |  |  |  | 4,346 |
INVESTMENTS IN SUBSIDIARIES AND JOINTLY-CONTROLLED ENTITIES |  |  |  |  |  | 1,163 |
ADDITIONS TO THE SEGMENT |  |  |  |  |  | 138 |
NET REVENUE |  |  |  |  |  | 708 |
OPERATING COSTS AND EXPENSES |  |  |  |  |  |  |
Personnel |  |  |  |  |  | (108) |
Employees' and managers' profit sharing |  |  |  |  |  | (7) |
Post-employment obligations |  |  |  |  |  | (27) |
Materials |  |  |  |  |  | (4) |
Outsourced services |  |  |  |  |  | (40) |
Operating provisions (reversals) |  |  |  |  |  | (12) |
Construction costs |  |  |  |  |  | (96) |
Other operating expenses, net |  |  |  |  |  | (17) |
Total cost of operation |  |  |  |  |  | (311) |
OPERATING COSTS AND EXPENSES |  |  |  |  |  | (311) |
Equity in earnings of unconsolidated investees, net |  |  |  |  |  | 231 |
OPERATING INCOME BEFORE FINANCE INCOME (EXPENSES) |  |  |  |  |  | 628 |
Finance income |  |  |  |  |  | 61 |
Finance expenses |  |  |  |  |  | (5) |
INCOME BEFORE INCOME TAX AND SOCIAL CONTRIBUTION TAX |  |  |  |  |  | 684 |
Income tax and social contribution tax |  |  |  |  |  | (133) |
Net income for the year from continuing operations |  |  |  |  |  | 551 |
Items that may be reclassified to profit or loss |  |  |  |  |  |  |
NET INCOME (LOSS) FOR THE YEAR |  |  |  |  |  | 551 |
NET INCOME FOR THE YEAR |  |  |  |  |  | 551 |
Equity holders of the parent |  |  |  |  |  | R$ 551 |
[1] | See note 2.8.
[2] | On March 31, 2018 Cemig Telecom assets and liabilities were merged into the Company.

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