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EARNINGS PER SHARE (EPS) - Basic (Details) - BRL (R$) R$ / shares in Units, R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Basic numerator |  |  |
Allocated net income (loss) available to common shareholders | R$ (120,267) | R$ (969,954) | R$ (1,541,242)
Allocated net income (loss) available to preferred shareholders | (239,093) | (1,920,857) | (3,010,196)
Allocated net income (loss) available to common and preferred shareholders | R$ (359,360) | R$ (2,890,811) | R$ (4,551,438)
Basic denominator |  |  |
Weighted-average outstanding shares, after deducting the average treasury shares for common share holders | 571,929,945 | 571,929,945 | 571,929,945
Weighted-average outstanding shares, after deducting the average treasury shares for Preferred share holders | 1,137,012,265 | 1,132,626,373 | 1,117,034,926
Earnings per share for common share (in R$) - Basic | R$ (0.21) | R$ (1.70) | R$ (2.69)
Earnings per share for preferred share (in R$) - Basic | R$ (0.21) | R$ (1.70) | R$ (2.69)

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- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2017-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_66&doctype=Standard -URIDate 2017-03-09 + Details
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