v3.20.4
Fair Value Measurements (Schedule Of Fair Value Adjustments Related To Non-Recurring Fair Value Measurements) (Details) - Nonrecurring Fair Value Measurements [Member] - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Loans Held For Sale [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, Fair Value Adjustment $ (8) $ (12)
Equity Investments Without a Readily Determinable Fair Value [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, Fair Value Adjustment 2 1
Foreclosed Property And Other Real Estate [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets, Fair Value Adjustment $ (10) $ (30)