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24. POST-EMPLOYMENT OBLIGATIONS (Details 1) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | R$ 17,022 | R$ 13,892 | R$ 12,663
Cost of current service | 26 | 17 | 15
Interest on actuarial obligation | 1,147 | 1,214 | 1,161
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 534 | 6 |
Due to changes in financial assumptions | (565) | 1,599 | 705
Due to adjustments based on experience | 148 | 160 | 161
Due to changes and adjustments | (117) | (2,941) | (1,064)
Benefits paid | (1,070) | (1,042) | (1,011)
Ending balance | 17,242 | 17,022 | 13,892
Pension plans and retirement supplement plans [member] |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 13,285 | 11,073 | 10,545
Cost of current service | 1 | 1 | 4
Interest on actuarial obligation | 887 | 963 | 959
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 135 | 6 |
Due to changes in financial assumptions | (375) | 2,058 | 467
Due to adjustments based on experience | 289 | 83 | (20)
Due to changes and adjustments | (49) | (2,147) | (447)
Benefits paid | (914) | (899) | (881)
Ending balance | 13,308 | 13,285 | 11,073
Health plan [member] |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 3,102 | 2,344 | 1,809
Cost of current service | 21 | 14 | 10
Interest on actuarial obligation | 215 | 208 | 172
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 395 |  |
Due to changes in financial assumptions | (152) | 667 | 402
Due to adjustments based on experience | (119) | 91 | 68
Due to changes and adjustments | (124) | (667) | (470)
Benefits paid | (143) | (131) | (118)
Ending balance | 3,319 | 3,102 | 2,344
Dental plan [member] |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 61 | 48 | 39
Cost of current service | 1 |  |
Interest on actuarial obligation | 4 | 5 | 4
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions | 4 |  |
Due to changes in financial assumptions | (4) | 10 | 8
Due to adjustments based on experience | 1 |  |
Due to changes and adjustments | (1) | (11) | (8)
Benefits paid | (3) | (2) | (3)
Ending balance | 64 | 61 | 48
Life insurance plan [member] |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 574 | 427 | 270
Cost of current service | 3 | 3 | 2
Interest on actuarial obligation | 41 | 38 | 25
Actuarial losses (gains): |  |  |
Due to changes in demographic assumptions |  |  |
Due to changes in financial assumptions | (34) | 117 | 140
Due to adjustments based on experience | (23) | (14) | 113
Due to changes and adjustments | 57 | (116) | (139)
Benefits paid | (10) | (10) | (9)
Ending balance | R$ 551 | R$ 574 | R$ 427

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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 2020-01-01 -Paragraph 141 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_141_c_ii&doctype=Standard -URIDate 2020-01-01 + 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 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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- 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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