| In Millionen CHF (US-GAAP) | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 
|---|---|---|---|---|---|---|---|---|---|---|
|   Nettoertrag  |   389  |   394  |   396  |   439  |   480  |   497  |   487  |   509  |   516  |   550  |  
|   Reingewinn  |   145  |   144  |   145  |   154  |   159  |   153  |   161  |   169  |   158  |   170  |  
|   Cost/Income Ratio  |   41.5%  |   42.5%  |   42.4%  |   44.0%  |   48.3%  |   49.8%  |   50.6%  |   50.6%  |   50.9%  |   48.1%  |  
|   Eigenkapital  |   799  |   848  |   885  |   933  |   1'091  |   1'027  |   1'200  |   1'274  |   1'250  |   1'285  |  
|   Eigenkapitalrendite  |   17.7%  |   17.4%  |   16.7%  |   16.9%  |   15.7%  |   13.8%  |   13.9%  |   13.7%  |   12.5%  |   13.4%  |  
|   Tier-1-Kapitalquote  |   19.8%  |   20.0%  |   19.2%  |   19.2%  |   16.3%  |   17.7%  |   18.9%  |   17.8%  |   17.2%  |   17.9%  |  
|   Forderungen gegenüber Kunden (Netto)  |   4'063  |   4'073  |   4'562  |   4'807  |   6'586  |   6'293  |   6'207  |   6'520  |   6'687  |   6'625  |  
|   Mitarbeitende (FTE)  |   715  |   705  |   735  |   783  |   1'045  |   928  |   916  |   929  |   902  |   812  |  
|   Ordentliche Dividende (in CHF)  |   3.35  |   3.45  |   3.55  |   3.75  |   3.75  |   3.75  |   3.85  |   3.95  |   4.00  |   4.25  |  
|   Ausserordentliche Dividende (in CHF)  |   
  |   1.00  |   
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