Retirement, Other Postretirement Benefits, And Defined Contribution Plans (Plan Assets, Asset Allocations Targets) (Details)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Domestic Equity Securities [Member] \| Non-Taxables [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	39.00%
Range, Minimum	34.00%
Range, Maximum	44.00%
Postretirement Asset Allocation	42.00%	40.00%
International Equity Securities [Member] \| Non-Taxables [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	26.00%
Range, Minimum	21.00%
Range, Maximum	31.00%
Postretirement Asset Allocation	25.00%	26.00%
Fixed Income Securities [Member] \| Non-Taxables [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	35.00%
Range, Minimum	30.00%
Range, Maximum	40.00%
Postretirement Asset Allocation	33.00%	34.00%
Other Securities [Member] \| Non-Taxables [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	0.00%
Range, Minimum	0.00%
Range, Maximum	5.00%
Postretirement Asset Allocation	0.00%	0.00%
Qualified Pension And Other Postretirement Plans [Member] \| Domestic Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	45.00%
Range, Minimum	34.00%
Range, Maximum	53.00%
Postretirement Asset Allocation	45.00%	46.00%
Qualified Pension And Other Postretirement Plans [Member] \| International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	20.00%
Range, Minimum	16.00%
Range, Maximum	24.00%
Postretirement Asset Allocation	19.00%	20.00%
Qualified Pension And Other Postretirement Plans [Member] \| Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	35.00%
Range, Minimum	31.00%
Range, Maximum	41.00%
Postretirement Asset Allocation	35.00%	33.00%
Qualified Pension And Other Postretirement Plans [Member] \| Other Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target	0.00%
Range, Minimum	0.00%
Range, Maximum	10.00%
Postretirement Asset Allocation	1.00%	1.00%

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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)

-URI http://asc.fasb.org/extlink&oid=28361610&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=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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