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EMPLOYEE BENEFITS - Post-employment health care benefit plan - Change in plan assets (Details) - Post-employment health care benefit - Fair value of plan assets - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
EMPLOYEE BENEFITS |  |  |
Fair value of the plan assets at the beginning of the year | R$ 0 | R$ 0 |
Contributions from sponsors | 12,572 | 12,463 | R$ 14,733
Contributions from participants | 1,556 | 2,212 | 2,206
Payment of benefits | (14,128) | (14,675) | (16,939)
Fair value of plan assets at the end of the year | R$ 0 | R$ 0 | R$ 0

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- Definition The decrease (increase) in net defined benefit liability (asset) resulting from contributions to a defined benefit plan by the employer. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_f&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_f&doctype=Standard -URIDate 2017-03-09 + Details
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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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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 140 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_140_a&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_g&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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- Details
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