Employee Benefits (Schedule Of Weighted Average Assumptions Used) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine net periodic benefit costs, Expected return on plan assets	7.00%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine benefit obligations, Discount rate	4.50%	5.30%	5.50%
Weighted average assumptions used to determine benefit obligations, Expected return on plan assets	7.00%	7.00%	7.00%
Weighted average assumptions used to determine benefit obligations, Rate of compensation increase	4.00%	4.00%	4.00%
Weighted average assumptions used to determine net periodic benefit costs, Discount rate	5.30%	5.50%	6.00%
Weighted average assumptions used to determine net periodic benefit costs, Expected return on plan assets	7.00%	7.00%	7.00%
Weighted average assumptions used to determine net periodic benefit costs, Rate of compensation increase	4.00%	4.00%	4.00%
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine benefit obligations, Discount rate	4.00%	4.50%	5.00%
Weighted average assumptions used to determine benefit obligations, Expected return on plan assets
Weighted average assumptions used to determine benefit obligations, Rate of compensation increase
Weighted average assumptions used to determine net periodic benefit costs, Discount rate	4.50%	5.00%	5.80%
Weighted average assumptions used to determine net periodic benefit costs, Expected return on plan assets
Weighted average assumptions used to determine net periodic benefit costs, Rate of compensation increase

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

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-Name Accounting Standards Codification

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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

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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

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-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

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

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-Name Statement of Financial Accounting Standard (FAS)

-Number 87

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-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

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-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

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

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- Definition

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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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-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.

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