v3.26.1
Note 9 - Income tax (Details Textual) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of geographical areas [line items]        
Pillar two legislation description Tenaris applies the IAS 12 exception regarding the recognition and disclosure of deferred tax assets and liabilities related to Pillar Two income taxes. Tenaris applies the exception regarding the recognition and disclosure of deferred tax assets and liabilities related to Pillar Two income taxes    
Current tax expense, related to Pillar Two income taxes   $ 20.7 $ 81.4  
Charge related to withholding taxes for intra group international operations   30.9 20.0 $ 164.3
Deferred Tax Income Recognised In Profit Or Loss   78.4 186.0 550.3
Charge related to pillar two   20.7 81.4  
Argentina and Mexico        
Disclosure of geographical areas [line items]        
Tax inflation adjustments   168.7 $ 368.2 $ 349.0
Luxembourg Ville        
Disclosure of geographical areas [line items]        
Corporate income tax rate     23.87% 24.94%
Consumption of deferred tax assets   $ 82.2 $ 86.9