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POST-EMPLOYMENT OBLIGATIONS (Details) - BRL (R$) R$ in Millions | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | --- | ---
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | R$ 5,692 | R$ 6,205 | R$ 6,843 | R$ 6,709
Pension plans and retirement supplement plans [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Fair value of plan assets | 9,198 | 9,378 | 10,420 | 10,366
Health plan [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 3,314 | 3,469 | 3,319 | 3,102
Dental plan [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 61 | 66 | R$ 64 | R$ 61
Actuarial assumption of expected rates of pension increases [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Present value of obligations | 14,778 | 15,561 |  |
Fair value of plan assets | (9,198) | (9,378) |  |
Net liabilities in the statement of financial position | 5,692 | 6,205 |  |
Actuarial assumption of expected rates of pension increases [member] | Initial net liabilities [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 5,580 | 6,183 |  |
Actuarial assumption of expected rates of pension increases [member] | Effect of asset ceiling [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 112 | 22 |  |
Actuarial assumption of expected rates of pension increases [member] | Pension plans and retirement supplement plans [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Present value of obligations | 11,404 | 12,026 |  |
Fair value of plan assets | (9,198) | (9,378) |  |
Net liabilities in the statement of financial position | 2,318 | 2,670 |  |
Actuarial assumption of expected rates of pension increases [member] | Pension plans and retirement supplement plans [member] | Initial net liabilities [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 2,206 | 2,648 |  |
Actuarial assumption of expected rates of pension increases [member] | Pension plans and retirement supplement plans [member] | Effect of asset ceiling [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 112 | 22 |  |
Actuarial assumption of expected rates of pension increases [member] | Health plan [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Present value of obligations | 3,314 | 3,469 |  |
Net liabilities in the statement of financial position | 3,314 | 3,469 |  |
Actuarial assumption of expected rates of pension increases [member] | Health plan [member] | Initial net liabilities [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | 3,314 | 3,469 |  |
Actuarial assumption of expected rates of pension increases [member] | Dental plan [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Present value of obligations | 60 | 66 |  |
Net liabilities in the statement of financial position | 60 | 66 |  |
Actuarial assumption of expected rates of pension increases [member] | Dental plan [member] | Initial net liabilities [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Net liabilities in the statement of financial position | R$ 60 | R$ 66 |  |

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- Definition The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_57_a&doctype=Standard -URIDate 2022-03-24 + 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 2022-03-24 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_57_a&doctype=Standard -URIDate 2022-03-24 + 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 2022-03-24 -Paragraph 57 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_57_a&doctype=Standard -URIDate 2022-03-24 + Details
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