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INVENTORIES - Changes in net realizable value of inventories (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Allowance for adjustment to net realizable value of inventories |  |  |
Balance at the beginning of the year | R$ (13,704) |  |
Balance at the end of the year | (39,308) | R$ (13,704) |
Inventories |  |  |
Allowance for adjustment to net realizable value of inventories |  |  |
Balance at the beginning of the year | (13,704) | (3,556) | R$ (28,813)
Provision for the year | (46,693) | (11,943) | (26,545)
Reversal of adjustment to net realizable value | 22,028 | 3,715 | 46,740
Loss of control by joint venture creation |  |  | 392
Assets held for sale |  | 1,049 | 881
Exchange rate variation | (939) | (871) | 3,789
Balance at the end of the year | R$ (39,308) | R$ (13,704) | R$ (3,556)

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- Definition The decrease in an allowance account for inventories adjustment to net realizable value resulting from the loss of control in a joint venture. + References No definition available. + Details
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- Definition The decrease in allowance for inventories adjustment to net realizable value through transfer to assets held for sale. + References No definition available. + Details
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