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, 2019 |
Dec. 31, 2018 |
|
| Loans Held For Sale [Member] | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Assets, Fair Value Adjustment | $ (12) | $ (13) |
| 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 | 1 | 8 |
| Foreclosed Property And Other Real Estate [Member] | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Assets, Fair Value Adjustment | $ (30) | $ (15) |