Benefit Plans (Summary Of Performance Shares Activity) (Details) - Performance Shares [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Nonvested, January 1 (in shares/awards)	144,424	139,940	145,277
Granted (in shares/awards)	45,403	51,221	49,093
Vested (in shares/awards)	(45,612)	(45,235)	(54,430)
Forfeited (in shares/awards)	0	(1,502)	0
Nonvested, December 31 (in shares/awards)	144,215	144,424	139,940
Instrument valuation based on shares of common stock, number of shares	1
Actual number of shares paid out upon vesting, minimum percentage of target shares	0.00%
Actual number of shares paid out upon vesting, maximum percentage of target shares	200.00%
2012 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Vested (in shares/awards)	(45,612)
Vested percentage of the target	167.50%
Cash and stock payout value	$ 5.1
Cash payout value	$ 3.2
Common stock shares from vested performance shares (in shares)	10,975
2011 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Vested (in shares/awards)		(45,235)
Vested percentage of the target		147.50%
Cash and stock payout value		$ 3.4
Cash payout value		$ 2.9
Common stock shares from vested performance shares (in shares)		4,810
2010 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Vested (in shares/awards)			(54,430)
Vested percentage of the target			197.50%
Cash and stock payout value			$ 4.8
Cash payout value			$ 4.4
Common stock shares from vested performance shares (in shares)			4,177