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EARNINGS (LOSS) PER SHARE (EPS) - Basic (Details) - BRL (R$) R$ / shares in Units, R$ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Basic numerator
Net income (loss) available to owners of parent	R$ 2,303,868	R$ (359,360)	R$ (2,890,811)
Basic denominator
Basic earnings/(loss) per share	R$ 1.35	R$ (0.21)	R$ (1.70)
Common shares
Basic numerator
Net income (loss) available to owners of parent	R$ 774,279	R$ (120,267)	R$ (969,954)
Basic denominator
Weighted-average outstanding shares, after deducting the average treasury shares	571,929,945	571,929,945	571,929,945
Basic earnings/(loss) per share	R$ 1.35	R$ (0.21)	R$ (1.70)
Preferred shares
Basic numerator
Net income (loss) available to owners of parent	R$ 1,529,589	R$ (239,093)	R$ (1,920,857)
Basic denominator
Weighted-average outstanding shares, after deducting the average treasury shares	1,129,851,598	1,137,012,265	1,132,626,373
Basic earnings/(loss) per share	R$ 1.35	R$ (0.21)	R$ (1.70)

X

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that shares or units have been outstanding to the total time in that period.

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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
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- Definition

The profit (loss) from continuing and discontinued operations attributable to owners of the parent. [Refer: Profit (loss)]

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