| **Employee Retirement Benefits (Expected Future Benefit Payments For Qualified Plan And SERP) (Details) $ in Millions** | Dec. 31, 2016 USD ($) |
|-------------------------------------------------------------------------------------------------------------------------|-----------------------|
| **Compensation and Retirement Disclosure [Abstract]**                                                                   |                  |
| Expected future benefit payments, 2017                                                                                  | $ 34                  |
| Expected future benefit payments, 2018                                                                                  | 23                    |
| Expected future benefit payments, 2019                                                                                  | 24                    |
| Expected future benefit payments, 2020                                                                                  | 26                    |
| Expected future benefit payments, 2021                                                                                  | 28                    |
| Expected future benefit payments, 2022 - 2026                                                                           | $ 148                 |

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| - References
No definition available.
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| - Definition
Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| - Definition
Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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