v3.25.4
FINANCIAL INSTRUMENTS & RISK - Financial Assets and Liabilities (Details) - CHF (SFr)
SFr in Millions
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Related party long-term payables        
Financial assets, carrying amount SFr 150.5 SFr 167.6    
Financial assets, at fair value 150.5 167.6    
Financial liabilities 5,156.8 5,334.6    
Liabilities arising from financing activities 6,577.7 6,450.3 SFr 7,402.2 SFr 7,274.5
Unadjusted Difference        
Related party long-term payables        
Liabilities arising from financing activities   6,386.4    
Derivatives and Third-Party Debt        
Related party long-term payables        
Financial liabilities 4,671.1 4,927.2    
Financial liabilities, at fair value 4,703.4 4,686.2    
Third-party debt        
Related party long-term payables        
Financial liabilities 4,337.2 4,676.8    
Financial liabilities at fair value through profit or loss, category | Derivatives, Current | Level 2        
Related party long-term payables        
Financial liabilities 73.1 179.3    
Financial liabilities, at fair value 73.1 179.3    
Financial liabilities at fair value through profit or loss, category | Derivatives, Noncurrent | Level 2        
Related party long-term payables        
Financial liabilities 648.0 421.1    
Financial liabilities, at fair value 648.0 421.1    
Financial liabilities at amortised cost, category | Third-party debt | Level 1        
Related party long-term payables        
Financial liabilities 3,950.0 4,326.8    
Financial liabilities, at fair value 3,982.3 4,085.8    
Financial assets at fair value through profit or loss, category | Derivatives, Current | Level 2        
Related party long-term payables        
Financial assets, carrying amount 140.9 162.5    
Financial assets, at fair value 140.9 162.5    
Financial assets at fair value through profit or loss, category | Derivatives, Noncurrent | Level 2        
Related party long-term payables        
Financial assets, carrying amount 9.6 5.1    
Financial assets, at fair value SFr 9.6 SFr 5.1