|
Financial Derivatives (Risk Participation Agreements Sold) (Details) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2011
|
Dec. 31, 2010
|
|---|---|---|
| Notional Amount of Credit Risk Derivatives | $ 304 | $ 761 |
|
Risk Participation Agreements Sold [Member]
|
||
| Notional Amount of Credit Risk Derivatives | 1,568 | 1,367 |
| Estimated Net Fair Value | $ (5) | $ (2) |
| Weighted-Average Remaining Maturity In Years of Risk Participation Agreements Sold | 7.5 | 2.0 |