Employee Benefit Plans (Asset Allocation Of Retirement Plan) (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan, Actual Plan Asset Allocations	100.00%		100.00%
Equity Securities [Member]
Defined Benefit Plan, Actual Plan Asset Allocations	61.00%	61.00%	68.00%
Expected Long-Term Rate of Return, Equity securities, Minimum	9.00%
Expected Long-Term Rate of Return, Equity securities, Maximum	9.50%
Asses allocation target, current year, minimum	40.00%
Asses allocation target, current year, maximum	70.00%
Debt Securities [Member]
Defined Benefit Plan, Actual Plan Asset Allocations	38.00%	34.00%	27.00%
Expected Long-Term Rate of Return, Debt securities, Minimum	4.00%
Expected Long-Term Rate of Return, Debt securities, Maximum	5.85%
Asses allocation target, current year, minimum	30.00%
Asses allocation target, current year, maximum	60.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan, Actual Plan Asset Allocations	1.00%	5.00%	5.00%
Expected Long-Term Rate of Return, Cash equivalents	0
Asses allocation target, current year, minimum	0.00%
Asses allocation target, current year, maximum	15.00%

Defined benefit plan, expected long-term rate of return, cash equivalents

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Defined benefit plan, expected long-term rate of return, debt securities, range maximum

+ References

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Defined benefit plan, expected long-term rate of return, debt securities, range minimum

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Defined benefit plan, expected long-term rate of return, equity securities, range maximum

+ References

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Defined benefit plan, expected long-term rate of return, equity securities, range minimum

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2446-114920

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(1)

-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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