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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, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Allowance for adjustment to net realizable value of inventories |  |  |
Balance at the beginning of the year | R$ (28,813) |  |
Balance at the end of the year | (3,556) | R$ (28,813) |
Inventories |  |  |
Allowance for adjustment to net realizable value of inventories |  |  |
Balance at the beginning of the year | (28,813) | (101,121) | R$ (66,363)
Provision for the year | (26,545) | (62,899) | (54,987)
Reversal of adjustment to net realizable value | 46,740 | 94,391 | 37,451
Loss of control by selling of subsidiary |  | 30,105 |
Loss of control by joint venture creation | 392 |  |
Assets held for sale | 881 |  |
Exchange rate variation | 3,789 | 10,711 | (17,222)
Balance at the end of the year | R$ (3,556) | R$ (28,813) | R$ (101,121)

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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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