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Benefit Plans (Summary Of Performance Shares Activity) (Details) - Performance Shares [Member] - USD ($) $ in Millions | 12 Months Ended
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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

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- Definition 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) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
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