Retirement, Other Postretirement Benefits, And Defined Contribution Plans (Actuarial Assumptions Used In Determining Net Periodic And Other Postretirement Benefit Obligation) (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Periodic Pension And Other Postretirement Benefit Costs [Member]
Weighted-average rate of increase in future compensation levels	4.23%	4.23%	4.23%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.75%	4.75%	4.75%
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Pre-65 Retirees [Member]
Assumed health care cost trend rate	7.10%	7.25%	7.50%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate	2023	2022	2022
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Post - 65 Retirees [Member]
Assumed health care cost trend rate	7.70%	7.00%	7.25%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate	2023	2022	2022
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Qualified Pension Plans [Member]
Blended weighted-average discount rate	4.27%	5.14%	4.36%
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Other Postretirement [Member]
Weighted-average discount rate	4.23%	5.05%	4.36%
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Non-Qualified Pension Plans [Member]
Weighted-average discount rate	3.61%	4.29%	3.37%
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Minimum [Member] \| Qualified Pension Plans [Member]
Weighted-average discount rate	4.03%	5.04%	4.31%
Net Periodic Pension And Other Postretirement Benefit Costs [Member] \| Maximum [Member] \| Qualified Pension Plans [Member]
Weighted-average discount rate	4.40%	5.26%	4.50%
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member]
Weighted-average rate of increase in future compensation levels	4.23%	4.23%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.75%	4.75%
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Pre-65 Retirees [Member]
Assumed health care cost trend rate	6.75%	7.10%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate	2024	2023
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Post - 65 Retirees [Member]
Assumed health care cost trend rate	7.55%	7.70%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate	2024	2023
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Qualified Pension Plans [Member]
Blended weighted-average discount rate	4.67%	4.27%
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Other Postretirement [Member]
Weighted-average discount rate	4.60%	4.23%
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Non-Qualified Pension Plans [Member]
Weighted-average discount rate	3.84%	3.61%
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Minimum [Member] \| Qualified Pension Plans [Member]
Weighted-average discount rate	4.51%	4.03%
Pension Postretirement Benefit Obligations And Other Postretirement Accumulated Postretirement Benefit Obligations [Member] \| Maximum [Member] \| Qualified Pension Plans [Member]
Weighted-average discount rate	4.79%	4.40%
Pension Assets [Member] \| Net Periodic Pension And Other Postretirement Benefit Costs [Member]
Expected long-term rate of return on plan assets	8.25%	8.50%	8.50%
Non-Taxables [Member] \| Net Periodic Pension And Other Postretirement Benefit Costs [Member]
Expected long-term rate of return on plan assets	8.05%	8.30%	8.50%
Taxable [Member] \| Net Periodic Pension And Other Postretirement Benefit Costs [Member]
Expected long-term rate of return on plan assets	6.25%	6.50%	6.50%

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate, Blended

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- Definition

The interest rate used to adjust for the time value of money.

+ 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 (k)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Health Care Cost Trend Rate
-URI http://asc.fasb.org/extlink&oid=6514820

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

The ultimate trend rate for health care costs.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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