Retirement Plans (Summary Of Asset Allocation) (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Asset allocations (in hundredths)	100.00%	100.00%
U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations (in hundredths)	44.00%	43.00%
Target allocations, minimum (in hundredths)	30.00%
Target allocations (in hundredths)	50.00%
Target allocations, maximum (in hundredths)	70.00%
International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations (in hundredths)	18.00%	16.00%
Target allocations, minimum (in hundredths)	0.00%
Target allocations (in hundredths)	20.00%
Target allocations, maximum (in hundredths)	30.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations (in hundredths)	26.00%	25.00%
Target allocations, minimum (in hundredths)	15.00%
Target allocations (in hundredths)	30.00%
Target allocations, maximum (in hundredths)	55.00%
Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations (in hundredths)	12.00%	16.00%
Target allocations, minimum (in hundredths)	0.00%
Target allocations (in hundredths)	0.00%
Target allocations, maximum (in hundredths)	5.00%

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

+ References

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

+ References

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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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