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26. EMPLOYEE BENEFITS (Details 17) - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of defined benefit plans [line items]
Effect on present value of obligations	R$ (36,627)	R$ (427,523)	R$ 147,728
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$ 248
Effect on present value of obligations	R$ (33,996)
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$ 8,150
Effect on present value of obligations	R$ 78,813
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$ (2,059)
Effect on present value of obligations	R$ (19,906)
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$ 660
Effect on present value of obligations	R$ 36,985
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$ (6,698)
Effect on present value of obligations	R$ (67,670)
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$ 2,040
Effect on present value of obligations	R$ 19,728

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- References

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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 2017-01-01
-Paragraph 141
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_d&doctype=Standard
-URIDate 2017-03-09

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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets. 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]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 141
-Subparagraph c
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_c_i&doctype=Standard
-URIDate 2017-03-09

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