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Post-Retirement Obligation - Summary of Expectation for Payment of Benefits (Detail) R$ in Millions | 12 Months Ended
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Dec. 31, 2017 BRL (R$)
Disclosure of defined benefit plans [line items] |
Estimate of payment of benefits | R$ 1,003
Pension plans and retirement supplement plans [member] |
Disclosure of defined benefit plans [line items] |
Estimate of payment of benefits | 875
Health plan [member] |
Disclosure of defined benefit plans [line items] |
Estimate of payment of benefits | 117
Dental plan [member] |
Disclosure of defined benefit plans [line items] |
Estimate of payment of benefits | 3
Life insurance [member] |
Disclosure of defined benefit plans [line items] |
Estimate of payment of benefits | R$ 8

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- Definition 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. + References No definition available. + Details
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- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 147 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_147_b&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_148_d_iii&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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- Details
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- Details
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