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21 Employees benefits (Details 4) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Summary of employee benefits [Line Items] |  |  |
Cost of service, net | R$ 4,608 | R$ 235,976 | R$ 209,817
Interest cost rates | 414,747 | 224,429 | 213,201
Expected return on the plan's assets | (187,317) | (192,965) | (179,449)
Amount received from State of Sao Paulo (undisputed) | (95,452) | (97,300) | (96,282)
Total expenses | 136,586 | 170,140 | 147,287
G1 Plan [member] |  |  |
Summary of employee benefits [Line Items] |  |  |
Cost of service, net | 4,608 | 8,609 | (22,431)
Interest cost rates | 208,485 | 224,429 | 213,201
Expected return on the plan's assets | (187,317) | (192,965) | (179,449)
Amount received from State of Sao Paulo (undisputed) | 0 | 0 | 0
Total expenses | 25,776 | 40,073 | 11,321
G0 plan [member] |  |  |
Summary of employee benefits [Line Items] |  |  |
Cost of service, net | 0 | 227,367 | 232,248
Interest cost rates | 206,262 | 0 | 0
Expected return on the plan's assets | 0 | 0 | 0
Amount received from State of Sao Paulo (undisputed) | (95,452) | (97,300) | (96,282)
Total expenses | R$ 110,810 | R$ 130,067 | R$ 135,966

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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan. [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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Balance Type: | debit
Period Type: | duration

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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 amount represents information related to amount received from GESP. + References No definition available. + Details
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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 No definition available. + 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 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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