Pension plan and other post-employment benefits (Details 2) R$ in Thousands	12 Months Ended
Dec. 31, 2025 BRL (R$)
P B S [Member]
IfrsStatementLineItems [Line Items]
Net actuarial liabilities (assets) on beginning balance	R$ (9,131)
Expense (revenue) recognized in income (loss)	(824)
Sponsor's contributions	3,115
Recognized actuarial (gains) or losses	442
Unrecognized actuarial (gains) or losses
Net actuarial liabilities (assets) on ending balance	(6,398)
P B S Assisted [Member]
IfrsStatementLineItems [Line Items]
Net actuarial liabilities (assets) on beginning balance	(2,337)
Expense (revenue) recognized in income (loss)	(255)
Sponsor's contributions
Recognized actuarial (gains) or losses	550
Unrecognized actuarial (gains) or losses
Net actuarial liabilities (assets) on ending balance	(2,042)
Administration Agreement [Member]
IfrsStatementLineItems [Line Items]
Net actuarial liabilities (assets) on beginning balance	(119)
Expense (revenue) recognized in income (loss)	(13)
Sponsor's contributions
Recognized actuarial (gains) or losses	(24)
Unrecognized actuarial (gains) or losses
Net actuarial liabilities (assets) on ending balance	(156)
P A M E C Asset Policy [Member]
IfrsStatementLineItems [Line Items]
Net actuarial liabilities (assets) on beginning balance	1,080
Expense (revenue) recognized in income (loss)	112
Sponsor's contributions	(99)
Recognized actuarial (gains) or losses	10
Unrecognized actuarial (gains) or losses
Net actuarial liabilities (assets) on ending balance	1,103
A E S Telecom [Member]
IfrsStatementLineItems [Line Items]
Net actuarial liabilities (assets) on beginning balance
Expense (revenue) recognized in income (loss)
Sponsor's contributions
Recognized actuarial (gains) or losses
Unrecognized actuarial (gains) or losses
Net actuarial liabilities (assets) on ending balance
Medical Plan [Member]
IfrsStatementLineItems [Line Items]
Net actuarial liabilities (assets) on beginning balance	2,381
Expense (revenue) recognized in income (loss)	366
Sponsor's contributions	(2)
Recognized actuarial (gains) or losses	637
Unrecognized actuarial (gains) or losses
Net actuarial liabilities (assets) on ending balance	R$ 3,382

The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 141
-Subparagraph c
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-URIDate 2024-03-27

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- Definition

The decrease (increase) in the net defined benefit liability (asset) resulting from the gain (loss) on changes in the effect of limiting a net defined benefit asset to the asset ceiling, excluding amounts included in interest income or expense. [Refer: Interest income (expense); Net defined benefit liability (asset); 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 iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_141_c_iv&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
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-URIDate 2024-03-27

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