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Post-Employment Benefits - Summary of Defined Benefit Contribution (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of defined benefit plans and defined contribution plans [Line Items] |  |  |
Estimated contribution | R$ 57 |  |
Contributions made | 69 | R$ 72 | R$ 149
Pension plan - FIU [member] |  |  |
Disclosure of defined benefit plans and defined contribution plans [Line Items] |  |  |
Estimated contribution | 47 |  |
Contributions made | 58 | 58 | 78
Pension plan - FUNBEP [member] |  |  |
Disclosure of defined benefit plans and defined contribution plans [Line Items] |  |  |
Estimated contribution | 10 |  |
Contributions made | R$ 11 | R$ 14 | R$ 71

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- Definition The amount of employer contributions to retirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2017-01-01 -Paragraph 35 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=26&date=2017-03-01&anchor=para_35_b_i&doctype=Standard -URIDate 2017-03-09 + 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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- Definition Disclosure of defined benefit plans and defined contribution plans [Line Items] + References No definition available. + Details
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