v3.26.1
Intangible assets (Details Narrative) - BRL (R$)
R$ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
IfrsStatementLineItems [Line Items]      
Right of use R$ 50,492,473 R$ 44,771,124 R$ 44,012,858
Average amortization rate 2.60% 2.80% 5.40%
Short-term contracts R$ 5,000    
Sao Lourenco [Member]      
IfrsStatementLineItems [Line Items]      
Amortization expenses   R$ 166,944  
Alto Tiete [Member]      
IfrsStatementLineItems [Line Items]      
Amortization expenses 2,715    
Concession agreement – URAE-1 [Member]      
IfrsStatementLineItems [Line Items]      
Right of use 154,449    
Concession Agreements [Member]      
IfrsStatementLineItems [Line Items]      
Right of use   338,740 R$ 374,679
U R A E 1 [Member]      
IfrsStatementLineItems [Line Items]      
Right of use R$ 79,924,407    
Leases Related To Concession Agreements And Program Contracts [Member]      
IfrsStatementLineItems [Line Items]      
Right of use   338,740  
Program contracts [Member]      
IfrsStatementLineItems [Line Items]      
Right of use   R$ 1,577,787