v3.26.1
Financial instruments and risk management - Exchange rate risk management (Details) - Currency risk
R$ in Thousands
6 Months Ended 12 Months Ended
Jun. 30, 2026
BRL (R$)
shares
Dec. 31, 2023
Dec. 31, 2025
BRL (R$)
Selling transactions in the futures markets      
Disclosure of detailed information about financial instruments [line items]      
Value at risk time horizon   24 months  
Probable (base value) | United States of America, Dollars | Cash and cash equivalents | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets R$ 14,364,448   R$ 11,919,897
Probable (base value) | United States of America, Dollars | Marketable securities | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets 9,241   427,329
Probable (base value) | United States of America, Dollars | Trade accounts receivable | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets 4,461,604   4,705,509
Probable (base value) | United States of America, Dollars | Trade accounts payable | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (1,280,825)   (1,075,590)
Probable (base value) | United States of America, Dollars | Loans and financing | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (65,052,093)   (70,357,356)
Probable (base value) | United States of America, Dollars | Other liabilities | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (64,223)   (66,446)
Probable (base value) | United States of America, Dollars | Derivative options | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets 2,628,095   979,706
Probable (base value) | United States of America, Dollars | Derivative swaps | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets 543,741   (851,428)
Probable (base value) | United States of America, Dollars | Derivative Non-Deliverable Forward (‘NDF’) Contracts | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets 5,623   24,355
Probable (base value) | United States of America, Dollars | Embedded derivatives | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets 157,605   112,058
Probable (base value) | United States of America, Dollars | Commodity Derivatives | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets R$ 130,992   R$ (34,379)
Possible 25%      
Disclosure of detailed information about financial instruments [line items]      
Closing foreign exchange rate, percentage of increase (decrease) 25.00%    
Possible 25% | United States of America, Dollars | Cash and cash equivalents | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets R$ (3,591,112)    
Possible 25% | United States of America, Dollars | Marketable securities | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets (2,310)    
Possible 25% | United States of America, Dollars | Trade accounts receivable | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets (1,115,401)    
Possible 25% | United States of America, Dollars | Trade accounts payable | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (320,206)    
Possible 25% | United States of America, Dollars | Loans and financing | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (16,263,023)    
Possible 25% | United States of America, Dollars | Other liabilities | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (16,056)    
Possible 25% | United States of America, Dollars | Derivative options | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (4,063,302)    
Possible 25% | United States of America, Dollars | Derivative swaps | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (3,953,051)    
Possible 25% | United States of America, Dollars | Derivative Non-Deliverable Forward (‘NDF’) Contracts | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (309,749)    
Possible 25% | United States of America, Dollars | Embedded derivatives | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (156,499)    
Possible 25% | United States of America, Dollars | Commodity Derivatives | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets R$ (32,700)    
Remote 50%      
Disclosure of detailed information about financial instruments [line items]      
Closing foreign exchange rate, percentage of increase (decrease) 50.00%    
Remote 50% | United States of America, Dollars | Cash and cash equivalents | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets R$ (7,182,224)    
Remote 50% | United States of America, Dollars | Marketable securities | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets (4,621)    
Remote 50% | United States of America, Dollars | Trade accounts receivable | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial assets (2,230,802)    
Remote 50% | United States of America, Dollars | Trade accounts payable | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (640,413)    
Remote 50% | United States of America, Dollars | Loans and financing | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (32,526,047)    
Remote 50% | United States of America, Dollars | Other liabilities | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Financial liabilities (32,112)    
Remote 50% | United States of America, Dollars | Derivative options | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (8,199,075)    
Remote 50% | United States of America, Dollars | Derivative swaps | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (7,831,912)    
Remote 50% | United States of America, Dollars | Derivative Non-Deliverable Forward (‘NDF’) Contracts | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (619,527)    
Remote 50% | United States of America, Dollars | Embedded derivatives | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets (312,997)    
Remote 50% | United States of America, Dollars | Commodity Derivatives | U.S. Dollar to Brazilian Real      
Disclosure of detailed information about financial instruments [line items]      
Derivative financial assets R$ (65,438)    
Probable      
Disclosure of detailed information about financial instruments [line items]      
Closing foreign exchange rate | shares 5.1766