Financial assets at fair value through profit or loss and designated at fair value through profit or loss - Securities (Details 1) - BRL (R$) R$ in Millions	Dec. 31, 2022	Dec. 31, 2021
Financial assets at carrying value [Member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, current	R$ 147,563	R$ 78,151
Cost and fair value of financial assets held for trading by maturity, non-current	241,951	287,435
Total	389,514	365,586
Financial assets at carrying value [Member] \| Non-stated maturity [Member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, current	39,137	33,781
Financial assets at carrying value [Member] \| Not later than one year [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, current	108,426	44,370
Financial assets at carrying value [Member] \| Later than one year and not later than five years [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, non-current	170,372	212,424
Financial assets at carrying value [Member] \| Later than five years and not later than ten years [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, non-current	49,186	51,434
Financial assets at carrying value [Member] \| Later than ten years [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, non-current	22,393	23,577
Financial assets at fair value, class [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, current	145,722	77,057
Cost and fair value of financial assets held for trading by maturity, non-current	237,817	284,866
Total	383,539	361,923
Financial assets at fair value, class [member] \| Non-stated maturity [Member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, current	37,223	32,853
Financial assets at fair value, class [member] \| Not later than one year [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, current	108,499	44,204
Financial assets at fair value, class [member] \| Later than one year and not later than five years [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, non-current	169,113	211,325
Financial assets at fair value, class [member] \| Later than five years and not later than ten years [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, non-current	47,916	50,688
Financial assets at fair value, class [member] \| Later than ten years [member]
IfrsStatementLineItems [Line Items]
Cost and fair value of financial assets held for trading by maturity, non-current	R$ 20,788	R$ 22,853

The amount of current financial assets measured at fair value through profit or loss classified as held for trading. [Refer: Financial assets at fair value through profit or loss, classified as held for trading]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_55&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-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-2017-en-b&anchor=para_8_a&doctype=Standard&book=b
-URIDate 2022-03-24

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- Definition

The amount of financial assets at fair value through profit or loss classified as held for trading. A financial asset is classified as held for trading if: (a) it is acquired principally for the purpose of selling it in the near term; (b) on initial recognition it is part of a portfolio of identified financial instruments that are managed together and for which there is evidence of a recent actual pattern of short-term profit-taking; or (c) it is a derivative (except for a derivative that is a financial guarantee contract or a designated and effective hedging instrument). [Refer: At fair value [member]; Financial assets at fair value through profit or loss]

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- Definition

The amount of non-current financial assets that are measured at fair value through profit or loss and that are classified as held for trading. [Refer: Financial assets at fair value through profit or loss, classified as held for trading]

+ References

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