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Pension and Other Postretirement Benefits (Schedule Of Portfolio Asset Mix) (Details) | Dec. 31, 2021 | Dec. 31, 2020
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Minimum | Domestic Equities | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 7.00% | 12.00%
Minimum | Domestic Equities | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%
Minimum | International Equities | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 3.00% | 6.00%
Minimum | International Equities | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%
Minimum | Fixed Income | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 69.00% |
Minimum | Fixed Income | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 20.00% |
Minimum | Real Estate [Member] | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Real Estate [Member] | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Minimum | Real Estate | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 0.00%
Minimum | Real Estate | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 0.00%
Minimum | Short-Term Investments | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%
Minimum | Short-Term Investments | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%
Minimum | Private Equity | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%
Minimum | Private Equity | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%
Maximum | Domestic Equities | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 27.00% | 32.00%
Maximum | Domestic Equities | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 55.00% | 55.00%
Maximum | International Equities | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 13.00% | 16.00%
Maximum | International Equities | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 25.00% | 25.00%
Maximum | Fixed Income | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 81.00% |
Maximum | Fixed Income | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 100.00% |
Maximum | Real Estate [Member] | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 3.00% |
Maximum | Real Estate [Member] | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |
Maximum | Real Estate | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 7.00%
Maximum | Real Estate | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 0.00%
Maximum | Short-Term Investments | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 10.00% | 10.00%
Maximum | Short-Term Investments | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 10.00% | 10.00%
Maximum | Private Equity | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 3.00% | 5.00%
Maximum | Private Equity | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% | 0.00%

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