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v3.8.0.1

20. Employees benefits (Details 7) | 12 Months Ended
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Dec. 31, 2017
Life expectation | Increase of 1 year |
SummaryOfEmployeeBenefitsLineItems [Line Items] |
Impact on present value of the defined benefit obligations | Increase of R$ 40,729
Life expectation | Decrease of 1 year |
SummaryOfEmployeeBenefitsLineItems [Line Items] |
Impact on present value of the defined benefit obligations | Decrease of R$ 41,838
Funded plan | Discount rate | Increase of 1.0% |
SummaryOfEmployeeBenefitsLineItems [Line Items] |
Impact on present value of the defined benefit obligations | Decrease of R$ 257,172
Funded plan | Discount rate | Decrease of 1.0% |
SummaryOfEmployeeBenefitsLineItems [Line Items] |
Impact on present value of the defined benefit obligations | Increase of R$ 309,440
Funded plan | Wage increase rate | Increase of 1.0% |
SummaryOfEmployeeBenefitsLineItems [Line Items] |
Impact on present value of the defined benefit obligations | Increase of R$ 33,484
Funded plan | Wage increase rate | Decrease of 1.0% |
SummaryOfEmployeeBenefitsLineItems [Line Items] |
Impact on present value of the defined benefit obligations | Decrease of R$ 29,143

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