v3.26.1
Goodwill Mortgage Servicing Rights (Commercial and Residential Mortgage Servicing Rights - Key Valuation Assumptions) (Details)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2026
USD ($)
Dec. 31, 2025
USD ($)
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]        
Fair value $ 3,816 $ 3,659    
Mortgage Servicing Rights | Commercial real estate        
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]        
Fair value $ 1,030 $ 1,021 $ 1,041 $ 1,085
Weighted-average life (years) 3 years 8 months 12 days 3 years 9 months 18 days    
Decline in fair value from 10% adverse change in prepayment rate $ 8 $ 8    
Decline in fair value from 20% adverse change in prepayment rate 15 16    
Decline in fair value from 10% adverse change in interest rate 31 30    
Decline in fair value from 20% adverse change in interest rate 61 61    
Mortgage Servicing Rights | Residential mortgage loans held for sale        
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]        
Fair value $ 2,786 $ 2,638 $ 2,523 $ 2,626
Weighted-average life (years) 7 years 6 months 7 years 8 months 12 days    
Decline in fair value from 10% adverse change in prepayment rate $ 67 $ 64    
Decline in fair value from 20% adverse change in prepayment rate $ 130 $ 124    
Weighted-average option adjusted spread 7.09% 7.34%    
Decline in fair value from 10% adverse change in adjusted spread $ 82 $ 82    
Decline in fair value from 20% adverse change in adjusted spread $ 160 $ 159    
Mortgage Servicing Rights | Constant prepayment rate | Commercial real estate        
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]        
Servicing asset, measurement input 0.0440 0.0443    
Mortgage Servicing Rights | Constant prepayment rate | Residential mortgage loans held for sale        
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]        
Servicing asset, measurement input 0.0681 0.0673    
Mortgage Servicing Rights | Discount rate | Commercial real estate        
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]        
Servicing asset, measurement input 0.1076 0.1060