v3.26.1
Fair Value Measurement (Schedule Of A Description Of The Valuation Technique, Unobservable Input, And Qualitative Information For The Company's Assets And Liabilities Classified As Level 3) (Details)
$ in Millions
Mar. 31, 2026
USD ($)
Dec. 31, 2025
USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Residential mortgage servicing rights, at fair value $ 105 $ 99
Junior subordinated debentures, at fair value 333 338
Residential mortgage servicing rights    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Residential mortgage servicing rights, at fair value 105 99
Junior subordinated debentures    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Junior subordinated debentures, at fair value 333 338
Level 3    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Residential mortgage servicing rights, at fair value 105 99
Junior subordinated debentures, at fair value $ 333 $ 338
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Weighted Average | Constant prepayment rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Servicing asset, measurement input 0.0766 0.0826
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Weighted Average | Discount rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Servicing asset, measurement input 0.1018 0.1020
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Minimum | Constant prepayment rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Servicing asset, measurement input 0.0568 0.0576
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Minimum | Discount rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Servicing asset, measurement input 0.0950 0.0950
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Maximum | Constant prepayment rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Servicing asset, measurement input 0.2931 0.3021
Level 3 | Discounted cash flow | Residential mortgage servicing rights | Maximum | Discount rate    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Servicing asset, measurement input 0.1633 0.1630
Level 3 | Discounted cash flow | Junior subordinated debentures | Weighted Average | Credit spread    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Debt instrument, measurement input 0.0308 0.0286
Level 3 | Discounted cash flow | Junior subordinated debentures | Minimum | Credit spread    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Debt instrument, measurement input 0.0215 0.0182
Level 3 | Discounted cash flow | Junior subordinated debentures | Maximum | Credit spread    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Debt instrument, measurement input 0.0406 0.0397