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TAX, CIVIL AND LABOR CLAIMS AND CONTINGENT ASSETS - Changes in Provisions (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Changes in the tax, labor and civil provisions : |  |  |
Balance at the beginning of the year | R$ 770,305 |  |
Reversal of contingent liabilities, net |  |  | R$ 929,711
Reversal of monetary update of contingent liabilities |  |  | (369,819)
Balance at the end of the year | 809,299 | R$ 770,305 |
Legal proceedings provision |  |  |
Changes in the tax, labor and civil provisions : |  |  |
Balance at the beginning of the year | 770,305 | 827,883 | 2,239,226
Additions | 249,868 | 177,684 | 527,543
Monetary correction | 70,788 | 85,626 | 77,257
Reversal of contingent liabilities, net |  |  | (929,711)
Reversal of monetary update of contingent liabilities |  |  | (369,819)
Reversal of accrued amounts | (282,239) | (319,719) | (715,081)
Foreign exchange effect on provisions in foreign currency | 577 | (1,169) | (201)
Loss of control by joint venture creation |  |  | (1,331)
Balance at the end of the year | R$ 809,299 | R$ 770,305 | R$ 827,883

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