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27. EMPLOYEE BENEFITS (Details 10) - BRL (R$) R$ in Thousands	12 Months Ended
	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)
Plan covering 35% of the average salary | 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$ 409
Effect on present value of obligations	R$ (13,281)
Plan covering 35% of the average salary | Salary growth
Disclosure of defined benefit plans [line items]
Sensitivity level	0.50%
Plan covering 35% of the average salary | Mortality table
Disclosure of defined benefit plans [line items]
Sensitivity level	0.50%
Effect on current service cost and on interest on actuarial obligations	R$ 1,439
Effect on present value of obligations	R$ 14,685
Plan covering 35% of the average salary | Benefit adjustment
Disclosure of defined benefit plans [line items]
Sensitivity level	1.00%
Effect on current service cost and on interest on actuarial obligations	R$ (1,052)
Effect on present value of obligations	R$ (10,680)
Plan covering 35% of the average salary | 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$ (458)
Effect on present value of obligations	R$ 15,342
Plan covering 35% of the average salary | Salary growth
Disclosure of defined benefit plans [line items]
Sensitivity level	(0.50%)
Plan covering 35% of the average salary | Mortality table
Disclosure of defined benefit plans [line items]
Sensitivity level	(0.50%)
Effect on current service cost and on interest on actuarial obligations	R$ (1,350)
Effect on present value of obligations	R$ (13,778)
Plan covering 35% of the average salary | Benefit adjustment
Disclosure of defined benefit plans [line items]
Sensitivity level	(1.00%)
Effect on current service cost and on interest on actuarial obligations	R$ 1,054
Effect on present value of obligations	R$ 10,706
Average salary supplementation plan | 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$ 1,650
Effect on present value of obligations	R$ (70,755)
Average salary supplementation plan | Salary growth
Disclosure of defined benefit plans [line items]
Sensitivity level	0.50%
Average salary supplementation plan | Mortality table
Disclosure of defined benefit plans [line items]
Sensitivity level	0.50%
Effect on current service cost and on interest on actuarial obligations	R$ 7,578
Effect on present value of obligations	R$ 79,305
Average salary supplementation plan | Benefit adjustment
Disclosure of defined benefit plans [line items]
Sensitivity level	1.00%
Effect on current service cost and on interest on actuarial obligations	R$ (4,877)
Effect on present value of obligations	R$ (50,807)
Average salary supplementation plan | 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$ (1,897)
Effect on present value of obligations	R$ 76,222
Average salary supplementation plan | Salary growth
Disclosure of defined benefit plans [line items]
Sensitivity level	(0.50%)
Average salary supplementation plan | Mortality table
Disclosure of defined benefit plans [line items]
Sensitivity level	(0.50%)
Effect on current service cost and on interest on actuarial obligations	R$ (7,079)
Effect on present value of obligations	R$ (74,101)
Average salary supplementation plan | Benefit adjustment
Disclosure of defined benefit plans [line items]
Sensitivity level	(1.00%)
Effect on current service cost and on interest on actuarial obligations	R$ 4,845
Effect on present value of obligations	R$ 50,468
Mixed supplementary benefit plan (Milenio Plan) | 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$ (502)
Effect on present value of obligations	R$ (50,666)
Mixed supplementary benefit plan (Milenio Plan) | Salary growth
Disclosure of defined benefit plans [line items]
Sensitivity level	0.50%
Effect on current service cost and on interest on actuarial obligations	R$ 252
Effect on present value of obligations	R$ 2,028
Mixed supplementary benefit plan (Milenio Plan) | Mortality table
Disclosure of defined benefit plans [line items]
Sensitivity level	0.50%
Effect on current service cost and on interest on actuarial obligations	R$ 5,720
Effect on present value of obligations	R$ 57,166
Mixed supplementary benefit plan (Milenio Plan) | Benefit adjustment
Disclosure of defined benefit plans [line items]
Sensitivity level	1.00%
Effect on current service cost and on interest on actuarial obligations	R$ (1,120)
Effect on present value of obligations	R$ (12,179)
Mixed supplementary benefit plan (Milenio Plan) | 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$ 316
Effect on present value of obligations	R$ 54,396
Mixed supplementary benefit plan (Milenio Plan) | Salary growth
Disclosure of defined benefit plans [line items]
Sensitivity level	(0.50%)
Effect on current service cost and on interest on actuarial obligations	R$ (223)
Effect on present value of obligations	R$ (1,792)
Mixed supplementary benefit plan (Milenio Plan) | Mortality table
Disclosure of defined benefit plans [line items]
Sensitivity level	(0.50%)
Effect on current service cost and on interest on actuarial obligations	R$ (5,232)
Effect on present value of obligations	R$ (52,366)
Mixed supplementary benefit plan (Milenio Plan) | Benefit adjustment
Disclosure of defined benefit plans [line items]
Sensitivity level	(1.00%)
Effect on current service cost and on interest on actuarial obligations	R$ 1,128
Effect on present value of obligations	R$ 12,165

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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.

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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
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-IssueDate 2018-01-01
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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
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