v3.25.4
Credit Concentrations - Credit Concentrations Included in Trading Cash Instruments and Investments (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
U.S. government and agency obligations    
Concentration Risk [Line Items]    
Concentration risk, credit risk, financial instrument, maximum exposure $ 391,750 $ 389,148
Concentration risk, credit risk, financial instrument, maximum exposure, as a percentage of total assets 21.70% 23.20%
Non-U.S. government obligations    
Concentration Risk [Line Items]    
Concentration risk, credit risk, financial instrument, maximum exposure $ 112,031 $ 74,496
Concentration risk, credit risk, financial instrument, maximum exposure, as a percentage of total assets 6.20% 4.40%