v3.20.4
Business Segments - Summary of Gross Loans by Segment and Loan and Allowance for Loan Losses (Detail) - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Segment Reporting Information [Line Items]      
Loans, gross $ 119,989 $ 110,345  
Allowance for loan losses (3,874) (1,441) $ (1,066)
Loans 116,115 108,904  
Investment Banking [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 27,866 27,035  
Allowance for loan losses (1,322) (470)  
Loans 26,544 26,565  
Global Markets [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 33,662 31,279  
Allowance for loan losses (448) (168)  
Loans 33,214 31,111  
Asset Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 17,345 17,486  
Allowance for loan losses (787) (385)  
Loans 16,558 17,101  
Consumer & Wealth Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 41,116 34,545  
Allowance for loan losses (1,317) (418)  
Loans 39,799 34,127  
Corporate [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 48,659 46,307  
Corporate [Member] | Investment Banking [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 27,866 27,035  
Corporate [Member] | Global Markets [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 13,248 11,852  
Corporate [Member] | Asset Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 7,545 7,420  
Real Estate [Member] | Global Markets [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 16,915 15,671  
Real Estate [Member] | Asset Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 9,125 9,030  
Other [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 4,174 4,792  
Other [Member] | Global Markets [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 3,499 3,756  
Other [Member] | Asset Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 675 1,036  
Wealth Management [Member] | Consumer & Wealth Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 33,023 27,940  
Installment [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 3,823 4,747  
Installment [Member] | Consumer & Wealth Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 3,823 4,747  
Credit Card Receivable [Member]      
Segment Reporting Information [Line Items]      
Loans, gross 4,270 1,858  
Credit Card Receivable [Member] | Consumer & Wealth Management [Member]      
Segment Reporting Information [Line Items]      
Loans, gross $ 4,270 $ 1,858