Employee Benefit Plans (Asset Allocation Of Retirement Plan) (Details)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Employee Benefit Plans [Abstract]
Asset Category, Equity securities	61.00%	68.00%	71.00%
Asset Category, Debt securities	34.00%	27.00%	29.00%
Asset Category, Cash equivalents	5	5	0
Expected Long-Term Rate of Return, Equity securities, Minimum	9.00%
Expected Long-Term Rate of Return, Equity securities, Maximum	9.50%
Expected Long-Term Rate of Return, Debt securities, Minimum	4.00%
Expected Long-Term Rate of Return, Debt securities, Maximum	5.85%
2011 Target Allocation, Equity securities, Minimum	40.00%
2011 Target Allocation, Equity securities, Maximum	70.00%
2011 Target Allocation, Debt securities, Minimum	30.00%
2011 Target Allocation, Debt securities, Maximum	60.00%
2011 Target Allocation, Cash equivalents, Minimum	0.00%
2011 Target Allocation, Cash equivalents, Maximum	15.00%
Total	100.00%	100.00%	100.00%

Defined Benefit Plan, Cash Equivalents

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The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ References

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

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The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

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Target allocation maximum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation minimum percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation maximum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

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