EQUITY - Operations with non-controlling interests (Details) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Capital
Effect of interest changes in subsidiaries	R$ (19,194)	R$ (2,252)	R$ (1,969,237)
Total Parent company's interest
Capital
Effect of interest changes in subsidiaries	2,504	4,153	(1,144,526)
Non-controlling interests
Capital
Acquisition of non-controlling interests			(837,437)
Changes in the Paraopeba- Fixed Income Investment Fund	(21,698)	(6,405)	12,726
Effect of interest changes in subsidiaries	R$ (21,698)	R$ (6,405)	R$ (824,711)

The increase (decrease) in equity through acquisition of non-controlling interests in subsidiaries.

No definition available.

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The increase (decrease) in the entity's equity resulting from the change in the equity of subsidiaries. [Refer: Subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_106_d&doctype=Standard
-URIDate 2017-03-09

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- Definition

The increase (decrease) in equity resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Equity]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_106_d&doctype=Standard
-URIDate 2017-03-09

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