TFA - Principal amounts outstanding / total assets - continuing involvement (Details 2) - CHF (SFr)
SFr in Millions
Dec. 31, 2021
Dec. 31, 2020
CMBS    
Principal amounts outstanding and total assets of SPEs resulting from continuing involvement    
Principal amount outstanding SFr 15,428 SFr 17,421
Total assets of SPE 23,205 24,455
RMBS    
Principal amounts outstanding and total assets of SPEs resulting from continuing involvement    
Principal amount outstanding 56,990 47,324
Total assets of SPE 56,990 47,863
Other asset-backed financings    
Principal amounts outstanding and total assets of SPEs resulting from continuing involvement    
Principal amount outstanding 24,856 24,968
Total assets of SPE 57,797 50,817
Bank | CMBS    
Principal amounts outstanding and total assets of SPEs resulting from continuing involvement    
Principal amount outstanding 15,428 17,421
Total assets of SPE 23,205 24,455
Bank | RMBS    
Principal amounts outstanding and total assets of SPEs resulting from continuing involvement    
Principal amount outstanding 56,990 47,324
Total assets of SPE 56,990 47,863
Bank | Other asset-backed financings    
Principal amounts outstanding and total assets of SPEs resulting from continuing involvement    
Principal amount outstanding 24,856 24,968
Total assets of SPE SFr 57,797 SFr 50,817