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21 Employees benefits (Details 1) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Summary of employee benefits [Line Items] |  |
Defined benefit obligation, beginning | R$ (6,113,349) | R$ (5,138,445)
Current service cost | (40,404) | (274,368)
Interest cost | (414,747) | (224,429)
Actuarial (gains)/losses recorded as other comprehensive income | 585,968 | (790,473)
Benefits paid | 320,011 | 314,366
Defined benefit obligation, ending | (5,662,521) | (6,113,349)
G1 Plan [member] |  |
Summary of employee benefits [Line Items] |  |
Defined benefit obligation, beginning | (3,067,094) | (2,532,338)
Current service cost | (40,404) | (47,001)
Interest cost | (208,485) | (224,429)
Actuarial (gains)/losses recorded as other comprehensive income | 64,637 | (392,876)
Benefits paid | 138,366 | 129,550
Defined benefit obligation, ending | (3,112,980) | (3,067,094)
G0 plan [member] |  |
Summary of employee benefits [Line Items] |  |
Defined benefit obligation, beginning | (3,046,255) | (2,606,107)
Current service cost | 0 | (227,367)
Interest cost | (206,262) | 0
Actuarial (gains)/losses recorded as other comprehensive income | 521,331 | (397,597)
Benefits paid | 181,645 | 184,816
Defined benefit obligation, ending | R$ (2,549,541) | R$ (3,046,255)

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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_a&doctype=Standard -URIDate 2020-01-01 + Details
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Balance Type: | credit
Period Type: | duration

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- Definition The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 57 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_57_a&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 141 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_b&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 141 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_g&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount represents information related to actuarial gains losses recorded as other comprehensive income. + References No definition available. + Details
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- Definition Its represents information related to summary of employee benefits. + References No definition available. + Details
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- Details
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- Details
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