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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)

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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 + Details
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