Financial assets at fair value through profit or loss and designated at fair value through profit or loss - Securities (Details 2) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
IfrsStatementLineItems [Line Items]
At Fair Value Through Profit or Loss	R$ 464,682	R$ 434,169
Financial assets at carrying value [Member]
IfrsStatementLineItems [Line Items]
At Fair Value Through Profit or Loss	1,505	3,075
Current	1,505	1,474
Non-current		1,601
Financial assets at carrying value [Member] \| Not later than one year [member]
IfrsStatementLineItems [Line Items]
Current	1,505	1,474
Financial assets at carrying value [Member] \| Later than one year and not later than five years [member]
IfrsStatementLineItems [Line Items]
Non-current		1,601
Financial assets at fair value, class [member]
IfrsStatementLineItems [Line Items]
At Fair Value Through Profit or Loss	1,560	3,044
Current	1,560	1,458
Non-current		1,586
Financial assets at fair value, class [member] \| Not later than one year [member]
IfrsStatementLineItems [Line Items]
Current	1,560	1,458
Financial assets at fair value, class [member] \| Later than one year and not later than five years [member]
IfrsStatementLineItems [Line Items]
Non-current		1,586
Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently, category [member]
IfrsStatementLineItems [Line Items]
Cost	1,505	3,075
Accumulated gain / (loss) reflected in income	55	(31)
At Fair Value Through Profit or Loss	1,560	3,044
Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently, category [member] \| Brazilian government securities [member]
IfrsStatementLineItems [Line Items]
Cost	1,505
Accumulated gain / (loss) reflected in income	55
At Fair Value Through Profit or Loss	R$ 1,560
Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently, category [member] \| Brazilian external debt bonds [Member]
IfrsStatementLineItems [Line Items]
Cost		3,075
Accumulated gain / (loss) reflected in income		(31)
At Fair Value Through Profit or Loss		R$ 3,044

The amount of current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 8
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_8_a&doctype=Standard
-URIDate 2022-03-24

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- Definition

The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

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- Definition

The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 20
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_20_a_i&doctype=Standard
-URIDate 2022-03-24

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- Definition

The amount of non-current financial assets measured at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

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- Definition

Financial assets at cost through profit or loss.

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