CECL (Details 9) - CHF (SFr)
SFr in Millions
Dec. 31, 2021
Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Other financial assets held at amortized cost, past due SFr 0 SFr 0
Other financial assets held at amortized cost, total 1,042 1,010
Bank    
Financing Receivable, Recorded Investment, Past Due [Line Items]    
Other financial assets held at amortized cost, total SFr 1,042 SFr 1,010