Pension Plans And Other Postretirement Benefit Plans (Changes In Level 3 Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Plan Asset Allocations	27.00%	27.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Plan Asset Allocations	58.00%	58.00%
Other Post-Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	$ 31,312	$ 29,732
Fair value of plan assets as of end of year	30,868	31,312
Other Post-Retirement Benefits [Member] \| Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	0
Fair value of plan assets as of end of year	$ 0	$ 0
Other Post-Retirement Benefits [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Plan Asset Allocations	60.00%	60.00%
Other Post-Retirement Benefits [Member] \| Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Plan Asset Allocations	40.00%	40.00%
Pension Plan And SERP [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	$ 539,311	$ 481,502
Fair value of plan assets as of end of year	517,234	539,311
Pension Plan And SERP [Member] \| Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	0
Fair value of plan assets as of end of year	0	0
Pension Plan And SERP [Member] \| Absolute Return [Member] \| Partnership And Closely Held Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	36,114
Fair value of plan assets as of end of year	38,302	36,114
Pension Plan And SERP [Member] \| Real Estate [Member] \| Common/Collective Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	21,303
Fair value of plan assets as of end of year	24,147	21,303
Pension Plan And SERP [Member] \| Real Estate [Member] \| Partnership And Closely Held Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	6,760
Fair value of plan assets as of end of year	9,941	6,760
Pension Plan And SERP [Member] \| Private Equity Funds [Member] \| Partnership And Closely Held Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year	73
Fair value of plan assets as of end of year	$ 73	$ 73

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930

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

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- Definition

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 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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