Post-Employment Obligations - Schedule of Income Statement (Details) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
IfrsStatementLineItems [Line Items]
Current service cost		R$ 7	R$ 11	R$ 18
Past service cost			(56)	(4)
Interest on the actuarial obligation		1,322	1,653	1,592
Expense in 2024		(1,159)	(352)	(696)
Pension Plans And Retirement Supplement Plan [Member]
IfrsStatementLineItems [Line Items]
Current service cost		1		2
Past service cost				(4)
Interest on the actuarial obligation		1,055	1,276	1,224
Expected return on the assets of the Plan		(842)	(1,004)	(941)
Expense in 2024		214	272	281
Health Plans [Member]
IfrsStatementLineItems [Line Items]
Current service cost		6	11	16
Past service cost			(55)
Interest on the actuarial obligation		262	370	361
Expense in 2024		268	326	377
Total [Member]
IfrsStatementLineItems [Line Items]
Current service cost	R$ 5	7	11	18
Past service cost			(56)	4
Interest on the actuarial obligation	1,528	1,322	1,653	1,592
Expected return on the assets of the Plan	(1,012)	(842)	(1,004)	(941)
Expense in 2024	R$ 521	487	604	665
Dental Plans [Member]
IfrsStatementLineItems [Line Items]
Current service cost
Past service cost			(1)
Interest on the actuarial obligation		5	7	7
Expense in 2024		R$ 5	R$ 6	R$ 7

Ifrs Statement Line Items

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- Definition

Past Service Cost

+ References

No definition available.

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- Definition

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 141
-Subparagraph c
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_c_iii&doctype=Standard
-URIDate 2024-03-27

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- Definition

The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 141
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_a&doctype=Standard
-URIDate 2024-03-27

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- Definition

The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 141
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_b&doctype=Standard
-URIDate 2024-03-27

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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plan assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [domain]; Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 141
-Subparagraph c
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_c_i&doctype=Standard
-URIDate 2024-03-27

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