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21 Employees benefits (Details 2) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Summary of employee benefits [Line Items] |  |  |
Fair value of the plan's assets, beginning | R$ 2,752,417 | R$ 2,168,436 |
Expected return on the plan assets | 187,317 | 192,965 | R$ 179,449
Expected Company's contributions | 36,010 | 36,968 |
Expected participants' contributions | 36,608 | 38,391 |
Benefits paid | (138,366) | (129,549) |
Actuarial gains/(losses) included in other comprehensive income (loss) | (80,059) | 445,206 | 113,869
Fair value of the plan's assets, ending | 2,793,927 | 2,752,417 | 2,168,436
(Deficit)/Surplus | (2,868,594) | (3,360,932) |
G1 Plan [member] |  |  |
Summary of employee benefits [Line Items] |  |  |
Fair value of the plan's assets, beginning | 2,752,417 | 2,168,436 |
Expected return on the plan assets | 187,317 | 192,965 | 179,449
Expected Company's contributions | 36,010 | 36,968 |
Expected participants' contributions | 36,608 | 38,391 |
Benefits paid | (138,366) | (129,549) |
Actuarial gains/(losses) included in other comprehensive income (loss) | (80,059) | 445,206 | 113,869
Fair value of the plan's assets, ending | 2,793,927 | 2,752,417 | 2,168,436
(Deficit)/Surplus | (319,053) | (314,677) |
G0 plan [member] |  |  |
Summary of employee benefits [Line Items] |  |  |
Fair value of the plan's assets, beginning | 0 | 0 |
Expected return on the plan assets | 0 | 0 | 0
Expected Company's contributions | 0 | 0 |
Expected participants' contributions | 0 | 0 |
Benefits paid | 0 | 0 |
Actuarial gains/(losses) included in other comprehensive income (loss) | 0 | 0 | 0
Fair value of the plan's assets, ending | 0 | 0 | R$ 0
(Deficit)/Surplus | R$ (2,549,541) | R$ (3,046,255) |

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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 141 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_f&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 20 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_20_a_i&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] + 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 decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plans assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [member]; Interest expense (income), 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 c -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_c_i&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The fair value of any plan assets, less the present value of the defined benefit obligation. [Refer: Plan assets [member]] + 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 amount represents information related to estimate of contributions expected to be paid to plan by company. + References No definition available. + Details
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- Definition The amount represents information related to payment from plan net defined denefit liability asset. + 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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