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33. FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details 2) - BRL (R$) R$ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of financial liabilities [line items]
Variation in fair value		R$ 48	R$ 187
Put option - SAAG [member]
Disclosure of financial liabilities [line items]
Balance	R$ 419	312	196
Variation in fair value			121
Adjustment to fair value	64	107
Reversals			(5)
Balance	R$ 483	R$ 419	R$ 312

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Adjustment to fair value of options.

+ References

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- Definition

Reversals derivative financial liabilities.

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- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 55
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-URIDate 2019-03-27

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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.

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- Definition

The increase (decrease) in the fair value measurement of liabilities. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2019-01-01
-Paragraph 93
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2019-en-r&anchor=para_93_e&doctype=Standard
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