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EMPLOYEE BENEFITS - Defined benefit pension plan - Actuarial gains and losses (Details) - Defined benefit pension plan - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Amounts recognized as actuarial gains and losses in the statement of comprehensive income |  |  |
Restriction recognized in Other Comprehensive Income | R$ (1,696) | R$ 3,065 | R$ (44,453)
Remeasurements recognized in Other Comprehensive Income | 1,639 | 80,817 | (11,927)
Fair value of plan assets |  |  |
Amounts recognized as actuarial gains and losses in the statement of comprehensive income |  |  |
Gain (loss) on remeasurement | (232,214) | (109,153) | 235,275
Present value of the defined benefit obligations |  |  |
Amounts recognized as actuarial gains and losses in the statement of comprehensive income |  |  |
Gain (loss) on remeasurement | R$ 235,549 | R$ 186,905 | R$ (202,749)

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- References No definition available. + Details
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- Definition The amount of other comprehensive income, before tax, related to gains (losses) on restrictions on defined benefit plans. + References No definition available. + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [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 c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_c&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The amount of other comprehensive income, before tax, related to gains (losses) on remeasurements of defined benefit plans, which comprise actuarial gains and losses; the return on plan assets, excluding amounts included in net interest on the net defined benefit liability (asset); and any change in the effect of the asset ceiling, excluding amounts included in net interest on the net defined benefit liability (asset). [Refer: Other comprehensive income, before tax; Defined benefit plans [member]; Plan assets [member]; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 91 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_91_b&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_7&doctype=Standard -URIDate 2017-03-09 + Details
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