v3.25.4
EMPLOYEE BENEFIT OBLIGAITONS - Movement in Defined Benefit Obligations (Details) - Defined benefit obligation - CHF (SFr)
SFr in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of net defined benefit liability (asset) [line items]    
Net defined benefit liability (asset) at beginning of period SFr 859.9 SFr 802.1
Included in the consolidated statements of income or loss    
Current service costs 21.0 19.5
Past service costs/(income) 0.1 (2.1)
Interest costs on defined benefit obligation 8.0 10.5
Administration costs and termination benefits 1.8 1.9
Settlements 0.0 0.0
Included in consolidated statements of other comprehensive income    
Demographic assumptions 0.0 0.0
Financial assumptions (21.1) 15.5
Experience adjustment 9.1 39.9
Other    
Employee contributions 19.8 20.1
Benefits paid/transferred (66.3) (47.5)
Net defined benefit liability (asset) at end of period SFr 832.3 SFr 859.9