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INCOME AND SOCIAL CONTRIBUTION TAXES - Tax Asset Not Booked (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Domestic |  |
INCOME AND SOCIAL CONTRIBUTION TAXES |  |
Unused tax losses for which no deferred tax asset recognised | R$ 312,741 | R$ 317,889
Foreign |  |
INCOME AND SOCIAL CONTRIBUTION TAXES |  |
Unused tax losses for which no deferred tax asset recognised | 1,137,548 | 857,215
Unused tax credits for which no deferred tax asset recognised | R$ 360,152 | R$ 349,072

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