v3.25.4
Share capital - Capital Structure (Details) - CHF (SFr)
SFr / shares in Units, SFr in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Treasury shares      
Treasury shares outstanding at beginning of period (10,899,773)    
Treasury shares outstanding at end of period (10,899,773) (10,899,773)  
Changes in equity      
Balance, beginning of period SFr 112,270 SFr 160,643 SFr 168,991
Proceeds from public offerings, net of underwriting fees and transaction costs   104 40,535
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs     2,650
Balance, end of period SFr 44,884 SFr 112,270 SFr 160,643
Nominal value per share (in CHF per share) SFr 0.02    
Common Shares      
Common shares      
Number of shares issued at beginning of period 111,310,150 104,441,787  
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs (in shares)   5,700,000  
Issuance of shares - incentive plans, net of transaction costs (in shares) 1,331,854 1,168,363  
Number of shares issued at end of period 112,642,004 111,310,150 104,441,787
Treasury shares      
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs (in shares)   5,700,000  
Treasury shares      
Common shares      
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs (in shares)   5,700,000  
Treasury shares      
Treasury shares outstanding at beginning of period (10,899,773) (5,243,958)  
Proceeds from public offerings, net of underwriting fees and transaction costs (in shares)   30,232  
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs (in shares)   5,700,000  
Issuance of shares - incentive plans, net of transaction costs (in shares)   13,953  
Treasury shares outstanding at end of period (10,899,773) (10,899,773) (5,243,958)
Share capital      
Changes in equity      
Balance, beginning of period SFr 2,226 SFr 2,089 SFr 1,797
Proceeds from public offerings, net of underwriting fees and transaction costs     286
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs   114  
Issuance of shares - incentive plans, net of transaction costs 27 23  
Balance, end of period 2,253 2,226 2,089
Share premium      
Changes in equity      
Balance, beginning of period 478,506 474,907 431,323
Proceeds from public offerings, net of underwriting fees and transaction costs   103 40,249
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs     2,631
Issuance of shares - incentive plans, net of transaction costs 3,357 3,496  
Balance, end of period 481,863 478,506 474,907
Treasury shares      
Changes in equity      
Balance, beginning of period (218) (105) (124)
Proceeds from public offerings, net of underwriting fees and transaction costs   1  
Proceeds from sale of treasury shares in public offerings, net of underwriting fees and transaction costs   (114) 19
Balance, end of period SFr (218) SFr (218) SFr (105)