| **Pension Plans And Other Post-Retirement Benefits (Schedule Of Assumptions Related To Pension And Other Postretirement Benefit Plans) (Details)** | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Expected return on plan assets                                                                                                                     | 7.25%           |   |   |
| Pension Benefits [Member]                                                                                                                          |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Discount rate                                                                                                                                      | 4.48%           | 4.20% | 5.12% |
| Expected return on plan assets                                                                                                                     | 7.25%           | 7.50% | 7.50% |
| Pension Benefits [Member] | Obligations [Member]                                                                                                   |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Discount rate                                                                                                                                      | 4.13%           | 4.48% |   |
| Pension Benefits [Member] | Minimum [Member]                                                                                                       |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Rate of compensation increase                                                                                                                      | 3.00%           | 3.00% | 4.00% |
| Pension Benefits [Member] | Minimum [Member] | Obligations [Member]                                                                                |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Rate of compensation increase                                                                                                                      | 3.00%           | 3.00% |   |
| Pension Benefits [Member] | Maximum [Member]                                                                                                       |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Rate of compensation increase                                                                                                                      | 4.00%           | 4.00% | 4.50% |
| Pension Benefits [Member] | Maximum [Member] | Obligations [Member]                                                                                |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Rate of compensation increase                                                                                                                      | 4.00%           | 4.00% |   |
| Other Postretirement Benefits [Member]                                                                                                             |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Discount rate                                                                                                                                      | 4.60%           | 4.17% | 5.12% |
| Health care cost trend rate                                                                                                                        | 7.00%           | 7.00% | 7.50% |
| Rate to which the cost trend is assumed to decline (the ultimate trend rate)                                                                       | 5.00%           | 5.00% | 5.00% |
| Year that the rate reaches the ultimate trend rate                                                                                                 | 2021            | 2019 | 2019 |
| Other Postretirement Benefits [Member] | Obligations [Member]                                                                                      |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Discount rate                                                                                                                                      | 4.25%           | 4.60% |   |
| Health care cost trend rate                                                                                                                        | 6.60%           | 7.00% |   |
| Rate to which the cost trend is assumed to decline (the ultimate trend rate)                                                                       | 5.00%           | 5.00% |   |
| Year that the rate reaches the ultimate trend rate                                                                                                 | 2020            | 2021 |   |
| Other Postretirement Benefits [Member] | Minimum [Member]                                                                                          |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Expected return on plan assets                                                                                                                     | 4.83%           | 5.00% | 5.00% |
| Other Postretirement Benefits [Member] | Maximum [Member]                                                                                          |            |   |   |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                   |            |   |   |
| Expected return on plan assets                                                                                                                     | 7.25%           | 7.50% | 7.50% |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The interest rate used to adjust for the time value of money for the plan.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512046Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Expected rate of compensation increases (for pay-related plans).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The ultimate trend rate for health care costs.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Defined Benefit Plan Ultimate Trend Rate
+ References
No definition available.
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| X                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                       |
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| X                                                                                                                               |
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| X                                                                                                                               |
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| X                                                                                                                                                                                                                 |
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