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EMPLOYEE BENEFITS - Other retirement and termination benefits (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Retirement and termination benefits |  |
EMPLOYEE BENEFITS |  |
Total obligation | R$ 23,876 | R$ 55,276

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- Definition The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard -URIDate 2017-03-09 + Details
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Balance Type: | credit
Period Type: | instant

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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. + Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |