Fixed assets (Details) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
IfrsStatementLineItems [Line Items]
Cost	R$ 23,386	R$ 22,031
Depreciation	(15,423)	(14,921)
Impairment	(196)	(147)
Residual	7,767	6,963
Disposals	3	3
Real Estates [Member]
IfrsStatementLineItems [Line Items]
Cost	7,132	7,372
Depreciation	(3,835)	(4,089)
Impairment	(151)	(110)
Residual	3,146	3,173
Real Estates [Member] \| Land [member]
IfrsStatementLineItems [Line Items]
Cost	1,199	1,127
Residual	1,199	1,127
Real Estates [Member] \| Building And Improvements [Member]
IfrsStatementLineItems [Line Items]
Cost	5,933	6,245
Depreciation	(3,835)	(4,089)
Impairment	(151)	(110)
Residual	R$ 1,947	R$ 2,046
Real Estates [Member] \| Building And Improvements [Member] \| Bottom of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	4.00%	4.00%
Real Estates [Member] \| Building And Improvements [Member] \| Top of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	10.00%	10.00%
Other Fixed Assets [Member]
IfrsStatementLineItems [Line Items]
Cost	R$ 16,254	R$ 14,659
Depreciation	(11,588)	(10,832)
Impairment	(45)	(37)
Residual	4,621	3,790
Other Fixed Assets [Member] \| Installations And Furniture [Member]
IfrsStatementLineItems [Line Items]
Cost	3,559	3,312
Depreciation	(2,655)	(2,463)
Impairment	(14)	(10)
Residual	R$ 890	R$ 839
Other Fixed Assets [Member] \| Installations And Furniture [Member] \| Bottom of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	10.00%	10.00%
Other Fixed Assets [Member] \| Installations And Furniture [Member] \| Top of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	20.00%	20.00%
Other Fixed Assets [Member] \| Computer equipment [member]
IfrsStatementLineItems [Line Items]
Cost	R$ 9,786	R$ 9,094
Depreciation	(7,659)	(7,170)
Impairment	(31)	(27)
Residual	R$ 2,096	R$ 1,897
Other Fixed Assets [Member] \| Computer equipment [member] \| Bottom of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	20.00%	20.00%
Other Fixed Assets [Member] \| Computer equipment [member] \| Top of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	50.00%	50.00%
Other Fixed Assets [Member] \| Other property, plant and equipment [member]
IfrsStatementLineItems [Line Items]
Cost	R$ 2,909	R$ 2,253
Depreciation	(1,274)	(1,199)
Residual	R$ 1,635	R$ 1,054
Other Fixed Assets [Member] \| Other property, plant and equipment [member] \| Bottom of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	10.00%	10.00%
Other Fixed Assets [Member] \| Other property, plant and equipment [member] \| Top of range [member]
IfrsStatementLineItems [Line Items]
Annual depreciation rates	20.00%	20.00%

The amount of contractual commitments for the acquisition of property, plant and equipment. [Refer: Property, plant and equipment]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2022-03-24
-Paragraph 74
-Subparagraph c
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-URIDate 2022-03-24

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- Definition

The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2022-03-24
-Paragraph 73
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The depreciation rate used for property, plant and equipment. [Refer: Property, plant and equipment]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2022-03-24
-Paragraph 73
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- Definition

The decrease in property, plant and equipment resulting from disposals. [Refer: Property, plant and equipment]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2022-03-24
-Paragraph 73
-Subparagraph e
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2022-en-r&anchor=para_73_e_ii&doctype=Standard
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- Definition

The amount of impairment loss recognised in profit or loss for property, plant and equipment. [Refer: Impairment loss recognised in profit or loss; Property, plant and equipment]

+ References

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- Definition

Cost Property Plant And Equipment.

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