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27. EMPLOYEE BENEFITS (Details 17) - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Disclosure of defined benefit plans [line items] |  |
Effect on present value of obligations | R$ (51,213) | R$ (36,627)
Post-employment healthcare benefits | Discount rate |  |
Disclosure of defined benefit plans [line items] |  |
Sensitivity level | 0.50% |
Effect on current service cost and on interest on actuarial obligations | R$ 909 |
Effect on present value of obligations | R$ (35,530) |
Post-employment healthcare benefits | Medical inflation |  |
Disclosure of defined benefit plans [line items] |  |
Sensitivity level | 1.00% |
Effect on current service cost and on interest on actuarial obligations | R$ 8,091 |
Effect on present value of obligations | R$ 84,560 |
Post-employment healthcare benefits | Mortality table |  |
Disclosure of defined benefit plans [line items] |  |
Sensitivity level | 1.00% |
Effect on current service cost and on interest on actuarial obligations | R$ (2,161) |
Effect on present value of obligations | R$ (22,582) |
Post-employment healthcare benefits | Discount rate |  |
Disclosure of defined benefit plans [line items] |  |
Sensitivity level | (0.50%) |
Effect on current service cost and on interest on actuarial obligations | R$ (992) |
Effect on present value of obligations | R$ 38,727 |
Post-employment healthcare benefits | Medical inflation |  |
Disclosure of defined benefit plans [line items] |  |
Sensitivity level | (1.00%) |
Effect on current service cost and on interest on actuarial obligations | R$ (6,925) |
Effect on present value of obligations | R$ (72,369) |
Post-employment healthcare benefits | Mortality table |  |
Disclosure of defined benefit plans [line items] |  |
Sensitivity level | (1.00%) |
Effect on current service cost and on interest on actuarial obligations | R$ 2,148 |
Effect on present value of obligations | R$ 22,451 |

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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [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 2018-01-01 -Paragraph 141 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_d&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plans assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [member]; Interest expense (income), net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph c -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c_i&doctype=Standard -URIDate 2018-03-16 + Details
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