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30. EMPLOYEE BENEFITS (Details 4) - Benefits of Pension Plans [member] - BRL (R$) R$ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of defined benefit plans [line items]
Cost of current service	R$ 968	R$ 1,093	R$ 1,169
Interest cost	236,551	283,487	304,132
Expected return on plan assets	(257,946)	(314,102)	(327,830)
Interest on the asset ceiling effect	21,737	21,502	16,340
Total costs / (income), net	R$ 1,310	R$ (8,020)	R$ (6,189)

X

- 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
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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from the gain (loss) on changes in the effect of limiting a net defined benefit asset to the asset ceiling, excluding amounts included in interest income or expense. [Refer: Interest income; Net defined benefit liability (asset); 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
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X

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2020-01-01
-Paragraph 141
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- Definition

The amount refers to expected return on plan assets net defined benefit liability asset.

+ References

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- Definition

The amount refers to income expense from defined benefit obligation.

+ References

No definition available.

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