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Pension and Other Postretirement Benefits (Schedule Of Portfolio Asset Mix) (Details) | Dec. 31, 2018 | Dec. 31, 2017
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Minimum | Domestic Equities | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 12.00% | 16.00%
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 | 6.00% | 8.00%
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 | 59.00% |
Minimum | Fixed Income | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 20.00% |
Minimum | Diversified Credit [Member] | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 0.00%
Minimum | Diversified Credit [Member] | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 0.00%
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%
Maximum | Domestic Equities | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 32.00% | 36.00%
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 | 16.00% | 18.00%
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 | 71.00% |
Maximum | Fixed Income | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 100.00% |
Maximum | Diversified Credit [Member] | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 13.00%
Maximum | Diversified Credit [Member] | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage |  | 0.00%
Maximum | Real Estate [Member] | Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 7.00% |
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 |  | 13.00%
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 | 15.00% | 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%

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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