Post-Employment Benefits - Summary of Defined Benefit Contribution (Detail) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disclosure of defined benefit plans and defined contribution plans [Line Items]
Estimated contribution	R$ 56
Contributions made	75	R$ 50
Retirement plan - FIU
Disclosure of defined benefit plans and defined contribution plans [Line Items]
Estimated contribution	34
Contributions made	43	45
Retiremente plan - FUNBEP
Disclosure of defined benefit plans and defined contribution plans [Line Items]
Estimated contribution	22
Contributions made	R$ 32	R$ 5

The amount of employer contributions to retirement benefit plans.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 26
-IssueDate 2021-01-01
-Paragraph 35
-Subparagraph b
-Clause i
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- Definition

The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 147
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_147_b&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 148
-Subparagraph d
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_148_d_iii&doctype=Standard
-URIDate 2021-03-24

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- Definition

Disclosure of defined benefit plans and defined contribution plans [Line Items]

+ References

No definition available.

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