Retirement Plans (Assumptions Used To Determine Our Benefit Obligations And Net Periodic Benefit Costs) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Compensation And Retirement Disclosure Line Items
Weighted average used to determine benefit obligations, Rate of increase in compensation levels, minimum	2.00%	2.00%
Weighted average used to determine benefit obligations, Rate of increase in compensation levels, maximum	9.00%	9.00%
Weighted average used to determine net cost for the year ended, Rate of increase in compensation levels, minimum	2.00%	2.00%	2.00%
Weighted average used to determine net cost for the year ended, Rate of increase in compensation levels, maximum	9.00%	9.00%	9.00%
Pension Benefits [Member]
Compensation And Retirement Disclosure Line Items
Weighted average used to determine benefit obligations for the year ended, Discount rate	5.22%	5.73%
Weighted average used to determine net cost for the year ended, Discount rate	5.73%	6.42%	6.48%
Weighted average used to determine net cost for the year ended, expected long-term rate of return on assets	8.37%	8.43%	8.08%
Other Post-Retirement Benefits [Member]
Compensation And Retirement Disclosure Line Items
Weighted average used to determine benefit obligations for the year ended, Discount rate	5.13%	5.54%
Weighted average used to determine net cost for the year ended, Discount rate	5.54%	6.18%	6.79%
Weighted average used to determine net cost for the year ended, expected long-term rate of return on assets	8.03%	8.03%	8.00%
Trend rate for next year	8.00%	8.00%
Ultimate trend rate	5.00%	5.00%
Year rate reaches ultimate trend rate	2019	2016

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Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate, Maximum

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- Definition

Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate Minimum

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- Definition

Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Rate Of Compensation Increase, Maximum

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- Definition

Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Rate Of Compensation Increase, Minimum

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- 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 Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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- Definition

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

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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)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

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Reference 4: 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=6512013

-Topic 715

-SubTopic 30

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph l

-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

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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- Definition

The ultimate trend rate for health care costs.

+ References

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-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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- Definition

The year when the ultimate health care cost trend rate is expected to be reached.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 5

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