Pension and other post-retirement benefits - Plan assets measured at fair value (Details 3) - CHF (SFr)
SFr in Millions
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value SFr 23,098 SFr 22,212  
Plan assets at fair value, measured at net asset value per share 3,523 3,084  
Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 19,296 18,000 SFr 17,790
Plan assets at fair value, measured at net asset value per share 3,032 2,590  
International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,802 4,212 4,111
Plan assets at fair value, measured at net asset value per share 491 494  
International | Other post-retirement defined benefit plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0 0
Level 1 | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,141 3,148  
Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 804 962  
Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,337 2,186  
Level 2 | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 14,920 14,536  
Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 13,946 13,004  
Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 974 1,532  
Level 3 | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444 1,351
Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444 1,351
Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Group equity securities and options      
Defined benefit plan, Disclosure      
Plan assets at fair value 3 77  
Group equity securities and options | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 5,264 5,320  
Plan assets at fair value, measured at net asset value per share 0 0  
Impact of exchange-traded futures not carried at fair value      
Plan Assets not carried at fair value (186) (462)  
Group equity securities and options | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 101 85  
Plan assets at fair value, measured at net asset value per share 57 52  
Group equity securities and options | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 71  
Group equity securities and options | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Group equity securities and options | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 5,264 5,249  
Group equity securities and options | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 44 33  
Group equity securities and options | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Group equity securities and options | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Cash and cash equivalents | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 313 458  
Plan assets at fair value, measured at net asset value per share 0 0  
Impact of exchange-traded futures not carried at fair value      
Plan Assets not carried at fair value (59) 462  
Cash and cash equivalents | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 110 264  
Plan assets at fair value, measured at net asset value per share 0 0  
Cash and cash equivalents | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 313 458  
Cash and cash equivalents | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 9 17  
Cash and cash equivalents | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Cash and cash equivalents | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 101 247  
Cash and cash equivalents | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Cash and cash equivalents | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Debt securities      
Defined benefit plan, Disclosure      
Plan assets at fair value 5 0  
Debt securities | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 6,784 5,884  
Plan assets at fair value, measured at net asset value per share 469 438  
Impact of exchange-traded futures not carried at fair value      
Plan Assets not carried at fair value 245    
Debt securities | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,531 3,813  
Plan assets at fair value, measured at net asset value per share 434 422  
Debt securities | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Debt securities | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,328 2,169  
Debt securities | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 6,315 5,446  
Debt securities | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 769 1,222  
Debt securities | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Debt securities | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Government debt securities | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,332 2,176  
Plan assets at fair value, measured at net asset value per share 0 0  
Government debt securities | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,328 2,169  
Government debt securities | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 4 7  
Government debt securities | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Corporate debt securities | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 6,784 5,884  
Plan assets at fair value, measured at net asset value per share 469 438  
Corporate debt securities | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,199 1,637  
Plan assets at fair value, measured at net asset value per share 434 422  
Corporate debt securities | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Corporate debt securities | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Corporate debt securities | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 6,315 5,446  
Corporate debt securities | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 765 1,215  
Corporate debt securities | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Corporate debt securities | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,554 3,239  
Plan assets at fair value, measured at net asset value per share 0 0  
Real estate | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,040 1,795  
Real estate | Level 3 | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444 1,351
Real estate | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444  
Real estate - direct | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444  
Plan assets at fair value, measured at net asset value per share 0 0  
Real estate - direct | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate - direct | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate - direct | Level 3 | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444 1,351
Real estate - direct | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,514 1,444  
Real estate - indirect | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,040 1,795  
Plan assets at fair value, measured at net asset value per share 0 0  
Real estate - indirect | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 20  
Plan assets at fair value, measured at net asset value per share 0 20  
Real estate - indirect | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate - indirect | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate - indirect | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,040 1,795  
Real estate - indirect | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate - indirect | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Real estate - indirect | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Alternative investments | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,381 3,099  
Plan assets at fair value, measured at net asset value per share 2,563 2,152  
Alternative investments | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Plan assets at fair value, measured at net asset value per share 0 0  
Alternative investments | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 491 433  
Alternative investments | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Alternative investments | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 327 514  
Alternative investments | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Alternative investments | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Alternative investments | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Private equity - alternative investments | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,431 1,794  
Plan assets at fair value, measured at net asset value per share 2,431 1,794  
Private equity - alternative investments | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Private equity - alternative investments | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Private equity - alternative investments | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Hedge funds | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 221 414  
Plan assets at fair value, measured at net asset value per share 0 1  
Hedge funds | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Plan assets at fair value, measured at net asset value per share 0 0  
Hedge funds | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Hedge funds | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Hedge funds | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 221 413  
Hedge funds | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Hedge funds | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Hedge funds | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Other alternative investments | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 729 891  
Plan assets at fair value, measured at net asset value per share 132 357  
Other alternative investments | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Plan assets at fair value, measured at net asset value per share 0 0  
Other alternative investments | Level 1 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 491 433  
Other alternative investments | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Other alternative investments | Level 2 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 106 101  
Other alternative investments | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Other alternative investments | Level 3 | Switzerland | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Other alternative investments | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Other investments, plan assets | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 87 77  
Plan assets at fair value, measured at net asset value per share 0 0  
Other investments, plan assets | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Other investments, plan assets | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 87 77  
Other investments, plan assets | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,802 4,212 4,111
Plan assets at fair value, measured at net asset value per share 491 494  
Bank | International | Other post-retirement defined benefit plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0 SFr 0
Bank | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,337 2,186  
Bank | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 974 1,532  
Bank | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Group equity securities and options | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 101 85  
Plan assets at fair value, measured at net asset value per share 57 52  
Bank | Group equity securities and options | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Group equity securities and options | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 44 33  
Bank | Group equity securities and options | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Cash and cash equivalents | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 110 264  
Plan assets at fair value, measured at net asset value per share 0 0  
Bank | Cash and cash equivalents | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 9 17  
Bank | Cash and cash equivalents | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 101 247  
Bank | Cash and cash equivalents | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Debt securities | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 3,531 3,813  
Plan assets at fair value, measured at net asset value per share 434 422  
Bank | Debt securities | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,328 2,169  
Bank | Debt securities | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 769 1,222  
Bank | Debt securities | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Government debt securities | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,332 2,176  
Plan assets at fair value, measured at net asset value per share 0 0  
Bank | Government debt securities | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 2,328 2,169  
Bank | Government debt securities | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 4 7  
Bank | Government debt securities | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Corporate debt securities | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 1,199 1,637  
Plan assets at fair value, measured at net asset value per share 434 422  
Bank | Corporate debt securities | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Corporate debt securities | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 765 1,215  
Bank | Corporate debt securities | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Real estate - indirect | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 20  
Plan assets at fair value, measured at net asset value per share 0 20  
Bank | Real estate - indirect | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Real estate - indirect | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Real estate - indirect | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Alternative investments | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Plan assets at fair value, measured at net asset value per share 0 0  
Bank | Alternative investments | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Alternative investments | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Bank | Alternative investments | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Hedge funds | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Plan assets at fair value, measured at net asset value per share 0 0  
Bank | Hedge funds | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Hedge funds | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Hedge funds | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Other alternative investments | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Plan assets at fair value, measured at net asset value per share 0 0  
Bank | Other alternative investments | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Other alternative investments | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value (27) (47)  
Bank | Other alternative investments | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Other investments, plan assets | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 87 77  
Plan assets at fair value, measured at net asset value per share 0 0  
Bank | Other investments, plan assets | Level 1 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 0 0  
Bank | Other investments, plan assets | Level 2 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value 87 77  
Bank | Other investments, plan assets | Level 3 | International | Defined benefit pension plans      
Defined benefit plan, Disclosure      
Plan assets at fair value SFr 0 SFr 0