Provisions for pensions and similar obligations (Details 15) R$ in Thousands	Dec. 31, 2017 BRL (R$)
Sensitivity (+) 1,0%
Effects
Effect on current service cost and interest on actuarial liabilities	R$ 57,001
Effects on present value of obligation	597,410
Sensitivity (-) 1,0%
Effects
Effect on current service cost and interest on actuarial liabilities	(63,510)
Effects on present value of obligation	R$ (665,700)

The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 145
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_145_a&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant