v3.25.4
Intangible assets -Schedule of Intangible Assets (Details) - CHF (SFr)
SFr in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period SFr 58.3 SFr 64.6
Additions 5.7 4.5
Amortization (9.8) (10.8)
Intangible assets and goodwill at end of the period 54.2 58.3
Cost    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 105.7 101.2
Intangible assets and goodwill at end of the period 111.3 105.7
Accumulated depreciation    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period (47.4) (36.6)
Intangible assets and goodwill at end of the period (57.1) (47.4)
Patents, licenses and other rights    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 47.5 50.9
Additions 2.7 1.4
Amortization (5.1) (4.7)
Intangible assets and goodwill at end of the period 45.1 47.5
Patents, licenses and other rights | Cost    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 71.8 70.4
Intangible assets and goodwill at end of the period 74.5 71.8
Patents, licenses and other rights | Accumulated depreciation    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period (24.3) (19.6)
Intangible assets and goodwill at end of the period (29.4) (24.3)
Software    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 9.0 11.9
Additions 3.1 3.0
Amortization (4.7) (6.0)
Intangible assets and goodwill at end of the period 7.3 9.0
Software | Cost    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 32.1 29.0
Intangible assets and goodwill at end of the period 35.0 32.1
Software | Accumulated depreciation    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period (23.1) (17.1)
Intangible assets and goodwill at end of the period (27.7) (23.1)
Goodwill    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 1.8 1.8
Additions 0.0 0.0
Amortization 0.0 0.0
Intangible assets and goodwill at end of the period 1.8 1.8
Goodwill | Cost    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 1.8 1.8
Intangible assets and goodwill at end of the period 1.8 1.8
Goodwill | Accumulated depreciation    
Reconciliation of changes in intangible assets other than goodwill [abstract]    
Intangible assets and goodwill at beginning of period 0.0 0.0
Intangible assets and goodwill at end of the period SFr 0.0 SFr 0.0