Retirement Benefits (Assumptions Used To Determine Net Periodic Benefit Cost) (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate at measurement date	4.50%	5.25%	5.75%
Expected return on plan assets	7.75%	8.00%	8.00%
Increase in future compensation	3.50%	3.50%	3.50%
Medical cost trend rate (initial)	0.00%	0.00%	0.00%
Medical cost trend rate (ultimate)	0.00%	0.00%	0.00%
Years to ultimate rate	0 years	0 years	0 years
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate at measurement date	4.50%	5.25%	5.75%
Expected return on plan assets	7.50%	7.75%	8.00%
Increase in future compensation	3.50%	3.50%	3.50%
Medical cost trend rate (initial)	5.50%	6.00%	6.50%
Medical cost trend rate (ultimate)	5.00%	5.00%	5.00%
Years to ultimate rate	1 year	2 years	3 years

The assumed initial health care cost trend rate used to measure the net periodic benefit costs.

No definition available.

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- Definition

The assumed ultimate health care cost trend rate used to measure the net periodic benefit costs.

+ References

No definition available.

+ Details

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- Definition

The assumed year when the ultimate health care cost trend rate is expected to be reached. Used to measure the net periodic benefit costs.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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).

+ References

+ Details

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- Details

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