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26. POST-EMPLOYMENT OBLIGATIONS (Details Narrative) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of defined benefit plans [line items] |  |  |  |
Expense amount recognized in the Statement of income |  | R$ 56 | R$ 68 | R$ 65
Estimate of contributions expected to be paid to plan for next annual reporting period | R$ 1,059 |  |  |
Description of insurance policy |  |  |  | On 2017, the Company changed its life insurance policy, resulting in reduction of the retirees’ capital insured by 20% at each 5-year interval, from aged 60, down to a minimum of 20%. These changes resulted in a reduction of R$ 619 in the post-employment obligations reported on December 31, 2017, with counterpart in the Statement of income in 2017.
Forluz Pension Fund [Member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Obligation for past actuarial deficits relating to pension fund |  | R$ 566 | 652 |
Inflation index rate |  | 6.00% |  |
Funded Benefit Plan ('Plan A') [Member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Benefit amount payable |  | R$ 550 | 378 |
Remuneratory interest applicable on outstanding balance |  | 6.00% |  |
Estimate of contributions expected to be paid to plan for next annual reporting period | 286 |  |  |
Postretirement Benefits Plan [Member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Expense amount recognized in the Statement of income |  | R$ 408 | 337 | R$ 391
Finance expenses |  | R$ 56 | R$ 68 | R$ 65
Health Plan And Dental Plan [Member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Actuarial assumption of expected rates of inflation |  |  | 1.00% |
Defined Contribution Plan [Member] |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |
Estimate of contributions expected to be paid to plan for next annual reporting period | R$ 79 |  |  |

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- Definition The expected rate of inflation that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2019-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_144&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The present value of the expected payments by a retirement benefit plan to existing and past employees, attributable to the service already rendered. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2019-01-01 -Paragraph 35 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=26&code=ifrs-tx-2019-en-r&anchor=para_35_d&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2019-01-01 -Paragraph 147 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_147_b&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2019-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_148_d_iii&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of post-employment benefit expense relating to defined contribution plans. Defined contribution plans are post-employment benefit plans under which an entity pays fixed contributions into a separate entity (a fund) and will have no legal or constructive obligation to pay further contributions if the fund does not hold sufficient assets to pay all employee benefits relating to employee service in the current and prior periods. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2019-01-01 -Paragraph 53 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_53&doctype=Standard -URIDate 2019-03-27 + Details
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