| **Employee Retirement Benefits (Expected Future Benefit Payments For Qualified Plan And SERP) (Details) $ in Millions** | Dec. 31, 2019 USD ($) |
|-------------------------------------------------------------------------------------------------------------------------|-----------------------|
| **Retirement Benefits [Abstract]**                                                                                      |                  |
| Expected future benefit payments, 2020                                                                                  | $ 31                  |
| Expected future benefit payments, 2021                                                                                  | 26                    |
| Expected future benefit payments, 2022                                                                                  | 25                    |
| Expected future benefit payments, 2023                                                                                  | 26                    |
| Expected future benefit payments, 2024                                                                                  | 28                    |
| Expected future benefit payments, 2025 - 2029                                                                           | $ 147                 |

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.
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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.
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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.
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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.
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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.
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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.
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