v3.24.0.1
Share capital - Narrative (Details) - CHF (SFr)
SFr / shares in Units, SFr in Millions
12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Disclosure of classes of share capital [line items]      
Share capital SFr 33.5 SFr 33.5  
Share capital, paid-in percentage 100.00%    
Proceeds on sale of treasury shares related to share-based compensation SFr 10.1 26.4 SFr 0.5
Sale of treasury shares 0.8 1.6 22.8
Treasury shares      
Disclosure of classes of share capital [line items]      
Sale of treasury shares SFr 0.8 SFr 1.6 SFr 22.8
Class A shares      
Disclosure of classes of share capital [line items]      
Number of shares registered (in shares) 299,998,125 299,998,125  
Par value per share (in CHF per share) SFr 0.10    
Class A shares | Treasury shares      
Disclosure of classes of share capital [line items]      
Sale of shares held by On in treasury (in shares) 2,273,239    
Purchase of On shares from employees (sell-to-cover) at current market price (in shares) 34,349    
Class B      
Disclosure of classes of share capital [line items]      
Number of shares registered (in shares) 345,437,500 345,437,500  
Par value per share (in CHF per share) SFr 0.01