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Benefit Plans (Summary Of Performance Unit Activity) (Details) - Performance Units [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Nonvested, January 1 (in shares/awards)	63,665	65,912
Granted (in shares/awards)	17,837	20,422
Vested (in shares/awards)	(22,845)	(20,751)
Forfeited (in shares/awards)	(451)	(958)
Nonvested, September 30 (in shares/awards)	58,206	64,625
2012 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Vested (in shares/awards)	(22,845)
Vested percentage of the target	167.50%
Aggregate payout value	$ 1.6
2011 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Vested (in shares/awards)		(20,751)
Vested percentage of the target		147.50%
Aggregate payout value		$ 1.2

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Costs and payments related to employee benefits and equity-based compensation, such as pension expense and contributions, other postretirement benefits expense and payments, stock or unit options expense, and amortization of restricted stock or unit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 230



-SubTopic 10



-Section 45



-Paragraph 28



-Subparagraph (a)



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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 718



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (c)(1)(iv)(3)



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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 718



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (c)(2)(iii)(1)



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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 718



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (c)(2)(i)-(ii)



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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB



-Name Accounting Standards Codification



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