v3.26.1
Mortgage Banking Activities, Assumptions and Sensitivity of Residential MSRs (Details) - Residential mortgage servicing rights [Member]
$ in Millions
6 Months Ended 12 Months Ended
Jun. 30, 2026
USD ($)
$ / loan
Dec. 31, 2025
USD ($)
$ / loan
Mar. 31, 2026
USD ($)
Jun. 30, 2025
USD ($)
Mar. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]            
Mortgage servicing rights, carried at fair value $ 5,343 $ 5,696 $ 5,608 $ 6,417 $ 6,536 $ 6,844
Expected weighted-average life (in years) 6 years 4 months 24 days 6 years 3 months 18 days        
Key assumptions [Abstract]            
Prepayment rate assumption 7.60% 8.00%        
Impact on fair value from 10% adverse change $ (146) $ (163)        
Impact on fair value from 25% adverse change $ (352) $ (394)        
Discount rate assumption 9.40% 9.10%        
Impact on fair value from 100 basis point increase $ (220) $ (243)        
Impact on fair value from 200 basis point increase $ (421) $ (465)        
Cost to service assumption ($ per loan) | $ / loan 89 96        
Impact on fair value from 10% adverse change $ (91) $ (106)        
Impact on fair value from 25% adverse change $ (227) $ (266)