Business developments (Details) - CHF (SFr)
SFr in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Business Acquisition        
Issued shares (in shares) 2,650,747,720 2,447,747,720 2,556,011,720 2,556,011,720
Other Revenue, Other Investments SFr 253 SFr 769 SFr 1,141  
Bank        
Business Acquisition        
Issued shares (in shares) [1] 4,399,680,200 4,399,680,200    
Other Revenue, Other Investments SFr 256 SFr 769 SFr 1,142  
[1] The Bank's total share capital is fully paid and consists of 4,399,680,200 registered shares as of December 31, 2021. Each share is entitled to one vote. The Bank has no warrants on its own shares outstanding.