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30. OPERATING COSTS AND EXPENSES (Details 3) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure Of Operating Provisions Reversals [line items] |  |  |  |
Estimated losses on doubtful accounts receivables |  | R$ 238 | R$ 264 | R$ 248
Estimated losses on other accounts receivables | [1] | 11 | (4) | 27
Estimated losses on accounts receivables from related parties | [2] | 688 |  |
Contingency provisions (reversals) |  |  |  |
Labor claims | [3] | 136 | 42 | 206
Civil | [3] | 24 | 13 | 27
Tax | [3] | 1,228 | (5) | 7
Environmental | [3] | (1) | 1 |
Regulatory | [3] | 1 | (2) | (3)
Other | [3] | 12 | 2 | (6)
Other provisions | [3] | 1,400 | 51 | 231
Operating provision (Reversals) | [3] | 2,337 | 311 | 506
Adjustment for losses |  |  |  |
Provision for losses |  | 64 | 155 | 348
Operating provision (reversals) and adjustment for losses , Total |  | 2,401 | 466 | 854
Written Put Options [Member] | RME and LEPSA [member] |  |  |  |
Adjustment for losses |  |  |  |
Provision for losses |  |  | 48 | 231
Written Put Options [Member] | S A A G lnvestimentos S A [member] |  |  |  |
Adjustment for losses |  |  |  |
Provision for losses |  | 64 | R$ 107 | 116
Written Put Options [Member] | Sonda Procwork Outsourcing Informatica ltda [Member] |  |  |  |
Adjustment for losses |  |  |  |
Provision for losses |  |  |  | R$ 1
[1] | The estimated losses on other accounts receivable are presented in the consolidated Statement of income as operating expenses.
[2] | Estimated losses on accounts receivable from Renova, as a result of the assessment of the jointly-controlled entity credit risk, which deteriorated in the current year.
[3] | The provisions for contingencies of the holding company are presented in the consolidated statement of income for the year as operating expenses.

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- Definition Environmental provision. + References No definition available. + Details
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- Definition Regulatory provisions. + References No definition available. + Details
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