AOCI - Additional share information (Details 2) - SFr / shares
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Common shares issued      
Common Stock, Shares, Issued, Beginning Balance 2,447,747,720 2,556,011,720 2,556,011,720
Issuance of common shares 203,000,000 0 0
Cancellation of repurchased shares 0 (108,264,000) 0
Common Stock, Shares, Issued, Ending Balance 2,650,747,720 2,447,747,720 2,556,011,720
Treasury shares      
Treasury Stock, Shares, Beginning Balance 41,602,841 119,761,811 5,427,691
Sale of treasury shares 2,053,309,578 1,222,417,138 795,576,688
Issuance of common shares relating to mandatory convertible notes 203,000,000 (0) (0)
Conversion of mandatory convertible notes 202,998,491 0 0
Repurchase of treasury shares 2,151,374,939 1,303,331,434 951,743,509
Cancellation of repurchased shares 0 108,264,000 0
Share-based compensation, net of tax 58,606,500 50,809,266 41,832,701
Treasury Stock, Shares, Ending Balance 81,063,211 41,602,841 119,761,811
Common shares outstanding 2,569,684,509 2,406,144,879 2,436,249,909
Par value (in CHF per share) SFr 0.04 SFr 0.04  
Authorized shares (in shares) [1] 3,100,747,720 3,100,747,720  
Unissued shares (in shares) 450,000,000 653,000,000  
Capital Instrument Reserved      
Treasury shares      
Unissued shares (in shares) 111,524,164 111,193,477  
Bank      
Common shares issued      
Common Stock, Shares, Issued, Beginning Balance [2] 4,399,680,200    
Common Stock, Shares, Issued, Ending Balance [2] 4,399,680,200 4,399,680,200  
Treasury shares      
Common shares outstanding [2] 4,399,680,200 4,399,680,200  
Par value (in CHF per share) [2] SFr 1.00 SFr 1.00  
[1] Includes issued shares and unissued shares (conditional, conversion and authorized capital).
[2] 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.