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28. OPERATING COSTS AND EXPENSES (Details 5) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Of Operating Costs And Expenses [line items] |  |  |  |
Leasing and rentals |  | R$ 11 |  | R$ 93
Advertising |  | 7 |  | 19
Own consumption of energy |  | 24 |  | 27
Subsidies and donations |  | 22 |  | 22
Onerous concession |  | 3 |  | 3
Insurance |  | 25 |  | 7
CCEE annual charge |  | 6 |  | 6
Net loss (gain) on deactivation and disposal of assets |  | 81 |  | 7
Forluz - Administrative running cost |  | 30 |  | 28
Collection agents |  | 86 |  | 78
Obligations deriving from investment contracts | [1] | 9 |  |
Taxes and charges |  | 7 |  | 9
Other expenses | [2] | (14) |  | 106
Other operating expenses (revenues), net |  | R$ 297 |  | R$ 405
Restated [member] |  |  |  |
Disclosure Of Operating Costs And Expenses [line items] |  |  |  |
Leasing and rentals |  |  | R$ 20 |
Advertising |  |  | 9 |
Own consumption of energy |  |  | 21 |
Subsidies and donations |  |  | 40 |
Onerous concession |  |  | 3 |
Insurance |  |  | 12 |
CCEE annual charge |  |  | 6 |
Net loss (gain) on deactivation and disposal of assets |  |  | 88 |
Forluz - Administrative running cost |  |  | 30 |
Collection agents |  |  | 88 |
Obligations deriving from investment contracts | [1] |  | 32 |
Taxes and charges |  |  | 10 |
Other expenses | [2] |  | 135 |
Other operating expenses (revenues), net |  |  | R$ 494 |
[1] | This refers to claims under the agreement made between Alianca Geracao, Vale S.A. and Cemig. The action is provisioned at the cost of R$119 (R$98 on December 31, 2019), of which Cemig is responsible for R$41 (R$32 on December 31, 2019).
[2] | Includes the impairment loss recognized for intangible asset relating to the authorization for wind power generation granted to Volta do Rio in the amount of R$22.

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