v3.26.1
Shareholders equity - Share capital (Details) - BRL (R$)
R$ / shares in Units, R$ in Thousands
6 Months Ended 9 Months Ended 12 Months Ended
Jun. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Disclosure of classes of share capital [line items]      
Share capital R$ 24,250,120   R$ 24,235,546
Proportion of ownership interest in subsidiary 100.00% 100.00%  
Common Stock Price R$ 39.75   R$ 51.45
Treasury (Note 27.2)      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 2.45% 2.23%  
Treasury (Note 27.2) | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 30,980,893   28,208,827
Share Capital      
Disclosure of classes of share capital [line items]      
Increase (decrease) through other changes, equity R$ 14,574    
Share capital 24,283,855    
Share issue related cost R$ 33,735    
Share Capital | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 1,264,117,615   1,264,117,615
Suzano Holding S.A.      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 29.08% 29.08%  
Suzano Holding S.A. | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 367,612,329   367,612,329
Controller      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 15.52% 15.51%  
Controller | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 196,144,533   196,065,636
Related persons      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 2.10% 2.54%  
Related persons | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 26,568,442   32,157,608
Alden Fundo de Investimento em Ações      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 2.15% 2.15%  
Alden Fundo de Investimento em Ações | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 27,154,744   27,154,744
Controlling Shareholders      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 48.85% 49.28% 49.28%
Controlling Shareholders | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 617,480,048   622,990,317
Other shareholders      
Disclosure of classes of share capital [line items]      
Proportion of ownership interest in subsidiary 48.70% 48.49%  
Other shareholders | Quantity      
Disclosure of classes of share capital [line items]      
Quantity 615,656,674   612,918,471