Retirement Plans (Summary Of Asset Allocation) (Details)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
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)	52.00%	51.00%
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%	21.00%
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)	30.00%	28.00%
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)	0.00%	0.00%
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=28361610&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)

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

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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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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=28361610&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=28361610&loc=d3e1928-114920

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