Pension plan and other post-employment benefits (Details 1) - BRL (R$) R$ in Thousands	Dec. 31, 2025	Dec. 31, 2024
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	R$ 53,262	R$ 55,173
Fair value of the assets of the plan	(75,740)	(81,658)
Excess present value of obligations over fair value of assets	(22,478)	(26,485)
Amount recognized in other comprehensive income	18,367	18,359
Net actuarial liabilities/(assets)	(4,111)	R$ (8,126)
P B S [Member]
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	30,892
Fair value of the assets of the plan	(49,062)
Excess present value of obligations over fair value of assets	(18,170)
Amount recognized in other comprehensive income	11,772
Net actuarial liabilities/(assets)	(6,398)
P B S Assisted [Member]
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	8,319
Fair value of the assets of the plan	(15,291)
Excess present value of obligations over fair value of assets	(6,972)
Amount recognized in other comprehensive income	4,930
Net actuarial liabilities/(assets)	(2,042)
Administration Agreement [Member]
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	67
Fair value of the assets of the plan	(254)
Excess present value of obligations over fair value of assets	(187)
Amount recognized in other comprehensive income	31
Net actuarial liabilities/(assets)	(156)
P A M E C Asset Policy [Member]
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	1,103
Fair value of the assets of the plan
Excess present value of obligations over fair value of assets	1,103
Amount recognized in other comprehensive income
Net actuarial liabilities/(assets)	1,103
A E S Telecom [Member]
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	9,499
Fair value of the assets of the plan	(11,133)
Excess present value of obligations over fair value of assets	(1,634)
Amount recognized in other comprehensive income	1,634
Net actuarial liabilities/(assets)
Medical Plan [Member]
IfrsStatementLineItems [Line Items]
Present value of the actuarial obligations	3,382
Fair value of the assets of the plan
Excess present value of obligations over fair value of assets	3,382
Amount recognized in other comprehensive income
Net actuarial liabilities/(assets)	R$ 3,382

The present value of the expected payments by a retirement benefit plan to existing and past employees, attributable to the service already rendered.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 26
-IssueDate 2024-01-01
-Paragraph 35
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2024-en-r&anchor=para_35_d&doctype=Standard
-URIDate 2024-03-27

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- Definition

The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 140
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_140_a&doctype=Standard
-URIDate 2024-03-27

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- Definition

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 57
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_57_a&doctype=Standard
-URIDate 2024-03-27

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