Pension Plans And Other Post-Retirement Benefits (Schedule Of Assumptions Related To Pension And Other Postretirement Benefit Plans) (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	7.75%
Pension Plans [Member] \| Benefit Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.17%	5.00%
Pension Plans [Member] \| Benefit Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.00%	5.75%	5.91%
Expected return on plan assets	7.75%	7.75%	8.00%
Pension Plans [Member] \| Minimum [Member] \| Benefit Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	4.00%	4.00%
Pension Plans [Member] \| Minimum [Member] \| Benefit Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	4.00%	4.00%	4.00%
Pension Plans [Member] \| Maximum [Member] \| Benefit Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	4.50%	4.50%
Pension Plans [Member] \| Maximum [Member] \| Benefit Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	4.50%	4.50%	4.50%
Other Postretirement Benefit Plans [Member] \| Benefit Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.17%	5.00%
Rate of compensation increase	4.00%	4.00%
Health care cost trend rate	8.00%	8.50%
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	2019	2019
Other Postretirement Benefit Plans [Member] \| Benefit Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase	4.00%	4.00%	4.00%
Health care cost trend rate	8.50%	9.00%	8.00%
Year that the rate reaches the ultimate trend rate	2019	2019	2016
Discount rate	5.00%	5.75%	5.91%
Rate of compensation increase	5.00%	5.00%	5.00%
Other Postretirement Benefit Plans [Member] \| Minimum [Member] \| Benefit Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	5.17%	5.17%	5.33%
Other Postretirement Benefit Plans [Member] \| Maximum [Member] \| Benefit Costs [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	7.75%	7.75%	8.00%

The interest rate used to adjust for the time value of money for the plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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=21915506&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

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- Definition

The interest rate used to adjust for the time value of money.

+ References

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- 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

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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- Definition

Expected rate of compensation increases (for pay-related plans).

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- Definition

The ultimate trend rate for health care costs.

+ References

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

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- Definition

Defined Benefit Plan Ultimate Trend Rate

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