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Schedule of changes in present value of defined benefit obligation (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
IfrsStatementLineItems [Line Items] |  |  |
Defined-benefit obligation at December 31, 2020 | R$ 17,242 | R$ 17,022 | R$ 13,892
Cost of current service | 27 | 26 | 18
Interest on actuarial obligation | 1,159 | 1,147 | 1,213
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 486 | 534 | 6
Due to changes in financial assumptions | (2,777) | (565) | 2,775
Due to adjustments based on experience | 1,005 | 148 | 160
Due to changes and adjustments | (1,286) | 117 | 2,941
Benefits paid | (1,166) | (1,070) | (1,042)
Past service cost (1) | (415) |  |
Defined-benefit obligation at December 31, 2021 | 15,561 | 17,242 | 17,022
Pension Plans And Retirement Supplement Plans [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Defined-benefit obligation at December 31, 2020 | 13,308 | 13,285 | 11,073
Cost of current service | 2 | 1 | 1
Interest on actuarial obligation | 883 | 887 | 963
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 378 | 135 | 6
Due to changes in financial assumptions | (2,393) | (375) | 2,058
Due to adjustments based on experience | 828 | 289 | 83
Due to changes and adjustments | (1,187) | 49 | 2,147
Benefits paid | (980) | (914) | (899)
Past service cost (1) |  |  |
Defined-benefit obligation at December 31, 2021 | 12,026 | 13,308 | 13,285
Health Plan [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Defined-benefit obligation at December 31, 2020 | 3,319 | 3,102 | 2,344
Cost of current service | 21 | 21 | 14
Interest on actuarial obligation | 232 | 215 | 208
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 122 | 395 |
Due to changes in financial assumptions | (252) | (152) | 576
Due to adjustments based on experience | 200 | (119) | 91
Due to changes and adjustments | 70 | 124 | 667
Benefits paid | (173) | (143) | (131)
Past service cost (1) |  |  |
Defined-benefit obligation at December 31, 2021 | 3,469 | 3,319 | 3,102
Dental Plan [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Defined-benefit obligation at December 31, 2020 | 64 | 61 | 48
Cost of current service | 1 | 1 |
Interest on actuarial obligation | 5 | 4 | 4
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 1 | 4 |
Due to changes in financial assumptions | (5) | (4) | 11
Due to adjustments based on experience | 3 | 1 |
Due to changes and adjustments | (1) | 1 | 11
Benefits paid | (3) | (3) | (2)
Past service cost (1) |  |  |
Defined-benefit obligation at December 31, 2021 | 66 | 64 | 61
Life Insurance Plan [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Defined-benefit obligation at December 31, 2020 | 551 | 574 | 427
Cost of current service | 3 | 3 | 3
Interest on actuarial obligation | 39 | 41 | 38
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | (15) |  |
Due to changes in financial assumptions | (127) | (34) | 130
Due to adjustments based on experience | (26) | (23) | (14)
Due to changes and adjustments | (168) | (57) | 116
Benefits paid | (10) | (10) | (10)
Past service cost (1) | (415) |  |
Defined-benefit obligation at December 31, 2021 |  | R$ 551 | R$ 574

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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2021-01-01 -Paragraph 141 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_c_ii&doctype=Standard -URIDate 2021-03-24 + Details
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2021-01-01 -Paragraph 140 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_140_a&doctype=Standard -URIDate 2021-03-24 + 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 2021-01-01 -Paragraph 141 -Subparagraph g -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_141_g&doctype=Standard -URIDate 2021-03-24 + Details
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