Pension plan obligations (Details 2) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	R$ 827,631	R$ (206,306)	R$ 288,392
Actuarial gains/(losses) recorded as other comprehensive income	(549,389)	202,889	(172,833)
Asset ceiling	(132,244)
Total gains/(losses)	145,998	(3,417)	115,559
Deferred income tax and social contribution - G1 Plan	(3,671)	(27,864)	15,710
Valuation adjustments to equity	142,327	(31,281)	131,269
G1 Plan [Member]
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	692,430	(120,934)	126,626
Actuarial gains/(losses) recorded as other comprehensive income	(549,389)	202,889	(172,833)
Asset ceiling	(132,244)
Total gains/(losses)	10,797	81,955	(46,207)
Deferred income tax and social contribution - G1 Plan	(3,671)	(27,864)	15,710
Valuation adjustments to equity	7,126	54,091	(30,497)
G0 Plan [Member]
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	135,201	(85,372)	161,766
Actuarial gains/(losses) recorded as other comprehensive income
Asset ceiling
Total gains/(losses)	135,201	(85,372)	161,766
Deferred income tax and social contribution - G1 Plan
Valuation adjustments to equity	R$ 135,201	R$ (85,372)	R$ 161,766

The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
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The decrease (increase) in the net defined benefit liability (asset) resulting from settlements. Settlements are transactions that eliminate all further legal or constructive obligations for part or all of the benefits provided under a defined benefit plan, other than a payment of benefits to, or on behalf of, employees that is set out in the terms of the plan and included in the actuarial assumptions. [Refer: Net defined benefit liability (asset); Defined benefit plans [domain]; Actuarial assumptions [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 141
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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 2024-01-01
-Paragraph 20
-Subparagraph a
-Clause i
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- Definition

The amount of other comprehensive income, before tax, related to gains (losses) on remeasurements of defined benefit plans, which comprise actuarial gains and losses; the return on plan assets, excluding amounts included in net interest on the net defined benefit liability (asset); and any change in the effect of the asset ceiling, excluding amounts included in net interest on the net defined benefit liability (asset). [Refer: Other comprehensive income; Defined benefit plans [domain]; Plan assets [member]; Net defined benefit liability (asset)] [Contrast: Decrease (increase) in net defined benefit liability (asset) resulting from gain (loss) on remeasurement in other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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