Pension plan obligations (Details 2) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	R$ 288,392	R$ 745,160	R$ 585,968
Actuarial gains/(losses) recorded as other comprehensive income	(172,833)	(237,492)	(80,059)
Total gains/(losses)	115,559	507,668	505,909
Deferred income tax and social contribution - G1 Plan	15,710	(60,292)	5,243
Valuation adjustments to equity	131,269	447,376	511,152
G 1 Plan [Member]
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	126,626	414,823	64,637
Actuarial gains/(losses) recorded as other comprehensive income	(172,833)	(237,492)	(80,059)
Total gains/(losses)	(46,207)	177,331	(15,422)
Deferred income tax and social contribution - G1 Plan	15,710	(60,292)	5,243
Valuation adjustments to equity	(30,497)	117,039	(10,179)
G 0 Plan [Member]
IfrsStatementLineItems [Line Items]
Actuarial gains/(losses) on obligations	161,766	330,337	521,331
Actuarial gains/(losses) recorded as other comprehensive income
Total gains/(losses)	161,766	330,337	521,331
Deferred income tax and social contribution - G1 Plan
Valuation adjustments to equity	R$ 161,766	R$ 330,337	R$ 521,331

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)]

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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 [member]; Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
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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
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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 [member]; 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

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