v3.26.1
Expected credit loss measurement - On-balance sheet financial assets subject to ECL (Detail) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Disclosure Of Credit Risk Exposure [Line Items]    
Total allowances and provisions $ (4,019) $ (3,982)
Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,125,443 1,098,962
Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,110,926 1,085,094
Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 215,716 209,858
Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 20,514 19,243
Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 83,553 83,656
Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 51,314 41,552
Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 667,391 658,760
Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 288,702 288,259
Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 94,239 93,076
Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 26,637 26,963
Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 23,739 23,941
Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 165,990 165,336
Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,535 2,408
Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 5,498 4,849
Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 9,097 8,753
Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,988 2,957
Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 72,437 72,025
of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,947 2,716
Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 14,517 13,868
Twelve-month expected credit losses | Stages 1 and 2    
Disclosure Of Credit Risk Exposure [Line Items]    
Total allowances and provisions (590) (575)
Twelve-month expected credit losses | Stages 1 and 2 | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,090,669 1,067,267
Twelve-month expected credit losses | Stages 1 and 2 | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,076,152 1,053,400
Twelve-month expected credit losses | Stages 1 and 2 | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 215,693 209,606
Twelve-month expected credit losses | Stages 1 and 2 | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 20,346 19,119
Twelve-month expected credit losses | Stages 1 and 2 | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 83,553 83,656
Twelve-month expected credit losses | Stages 1 and 2 | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 51,314 41,552
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 634,006 628,914
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 274,962 277,176
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 86,428 87,650
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 23,250 23,146
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 19,718 19,984
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 165,623 164,890
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,934 1,860
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 4,726 3,570
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 8,145 7,609
Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,760 2,699
Twelve-month expected credit losses | Stages 1 and 2 | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 71,241 70,552
Twelve-month expected credit losses | Stages 1 and 2 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,806 2,567
Twelve-month expected credit losses | Stages 1 and 2 | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 14,517 13,868
Lifetime expected credit losses | Stages 1 and 2    
Disclosure Of Credit Risk Exposure [Line Items]    
Total allowances and provisions (698) (661)
Lifetime expected credit losses | Stages 1 and 2 | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 29,705 26,911
Lifetime expected credit losses | Stages 1 and 2 | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 29,705 26,911
Lifetime expected credit losses | Stages 1 and 2 | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 23 252
Lifetime expected credit losses | Stages 1 and 2 | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 163 124
Lifetime expected credit losses | Stages 1 and 2 | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Lifetime expected credit losses | Stages 1 and 2 | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 28,591 25,287
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 12,069 9,635
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 7,396 5,307
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,845 2,890
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,623 2,551
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 169
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 550 501
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 772 1,274
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 883 1,025
Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 121 130
Lifetime expected credit losses | Stages 1 and 2 | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 927 1,247
Lifetime expected credit losses | Stages 1 and 2 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 48 53
Lifetime expected credit losses | Stages 1 and 2 | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Lifetime expected credit losses | Stage 3    
Disclosure Of Credit Risk Exposure [Line Items]    
Total allowances and provisions (2,731) (2,746)
Lifetime expected credit losses | Stage 3 | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 5,068 4,784
Lifetime expected credit losses | Stage 3 | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 5,068 4,784
Lifetime expected credit losses | Stage 3 | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Lifetime expected credit losses | Stage 3 | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 5 0
Lifetime expected credit losses | Stage 3 | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Lifetime expected credit losses | Stage 3 | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Lifetime expected credit losses | Stage 3 | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 4,794 4,559
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,671 1,448
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 415 119
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 543 928
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,399 1,406
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 368 276
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 51 47
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 6
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 69 119
Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 106 129
Lifetime expected credit losses | Stage 3 | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 269 225
Lifetime expected credit losses | Stage 3 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 93 95
Lifetime expected credit losses | Stage 3 | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Gross carrying amount | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 288,850 288,393
Gross carrying amount | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 94,327 93,145
Gross carrying amount | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 27,537 27,973
Gross carrying amount | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 25,184 25,246
Gross carrying amount | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 166,064 165,466
Gross carrying amount | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,588 2,456
Gross carrying amount | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 5,624 4,986
Gross carrying amount | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 9,109 8,771
Gross carrying amount | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 3,159 3,124
Gross carrying amount | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,982 2,750
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 275,003 277,220
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 86,454 87,676
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 23,354 23,263
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 19,810 20,064
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 165,628 164,896
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,941 1,867
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 4,736 3,593
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 8,152 7,618
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,789 2,718
Gross carrying amount | Twelve-month expected credit losses | Stages 1 and 2 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,809 2,571
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 12,092 9,653
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 7,422 5,337
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,946 2,984
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,709 2,632
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 169
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 564 513
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 772 1,274
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 887 1,033
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 146 154
Gross carrying amount | Lifetime expected credit losses | Stages 1 and 2 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 49 54
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,755 1,520
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 451 132
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 1,238 1,726
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 2,666 2,550
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 436 401
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 83 76
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 116 118
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 69 119
Gross carrying amount | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 224 252
Gross carrying amount | Lifetime expected credit losses | Stage 3 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 124 125
Allowance for expected credit loss | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (3,576) (3,635)
Allowance for expected credit loss | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (3,576) (3,635)
Allowance for expected credit loss | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (271) (262)
Allowance for expected credit loss | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (3) (14)
Allowance for expected credit loss | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (1) (1)
Allowance for expected credit loss | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (3,162) (3,236)
Allowance for expected credit loss | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (148) (134)
Allowance for expected credit loss | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (89) (68)
Allowance for expected credit loss | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (767) (1,009)
Allowance for expected credit loss | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (1,445) (1,305)
Allowance for expected credit loss | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (74) (130)
Allowance for expected credit loss | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (53) (48)
Allowance for expected credit loss | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (141) (136)
Allowance for expected credit loss | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (11) (17)
Allowance for expected credit loss | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (171) (167)
Allowance for expected credit loss | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (138) (122)
Allowance for expected credit loss | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (35) (34)
Allowance for expected credit loss | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (398) (392)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (398) (392)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 (9)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (1) (1)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (365) (352)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (41) (44)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (26) (26)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (104) (117)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (92) (80)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (5) (6)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (7) (7)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (9) (8)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (7) (9)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (29) (19)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (31) (29)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (4) (3)
Allowance for expected credit loss | Twelve-month expected credit losses | Stages 1 and 2 | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (576) (546)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (576) (546)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (271) (262)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (3) (5)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (286) (271)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (23) (18)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (26) (30)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (101) (94)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (86) (81)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (13) (12)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (4) (8)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (25) (24)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (15) (9)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (1) (1)
Allowance for expected credit loss | Lifetime expected credit losses | Stages 1 and 2 | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Total on-balance sheet financial assets in scope of ECL requirements    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (2,603) (2,697)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Total financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (2,603) (2,697)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Cash and balances at central banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Amounts due from banks    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Receivables from securities financing transactions measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Cash collateral receivables on derivative instruments    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (2,511) (2,613)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Private clients with mortgages    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (84) (72)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Real estate financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (37) (12)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Large corporate clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (562) (798)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: SME clients    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (1,267) (1,144)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Lombard    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (69) (124)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Credit cards    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (33) (29)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Commodity trade finance    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (131) (128)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Ship / aircraft financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets 0 0
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Loans and advances to customers | of which: Consumer financing    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (118) (123)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Other financial assets measured at amortized cost    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (91) (84)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | of which: Loans to financial advisors    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets (31) (30)
Allowance for expected credit loss | Lifetime expected credit losses | Stage 3 | Financial assets measured at fair value through other comprehensive income    
Disclosure Of Credit Risk Exposure [Line Items]    
Financial assets $ 0 $ 0