Retirement Benefits (Estimated FV Of Assets And Liabilities Measured And Recorded At FV On A Recurring Basis Postretirement) (Details) (Other Postretirement Benefit Plans Defined Benefit [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	$ 21.2	$ 19.3	$ 21.6	$ 20.7
Municipal Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	17.9	16.8
Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	2.6	1.8
Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	0.7	0.7
Fair Value Inputs Level1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	0.7	0.7
Fair Value Inputs Level1 [Member] | Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	0.7	0.7
Fair Value Inputs Level2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	20.5	18.6
Fair Value Inputs Level2 [Member] | Municipal Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	17.9	16.8
Fair Value Inputs Level2 [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	2.6	1.8
Fair Value Inputs Level2 [Member] | Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets are recorded at fair value	$ 0