Income Taxes (Schedule Of Components Of Income Tax Expense) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Income Tax Expense/Benefit [Line Items]
Current federal income taxes	$ (15.9)	$ (85.8)	$ (24.7)
Current state income taxes	(9.6)	7.8	(3.5)
Total current income taxes	(25.5)	(78.0)	(28.2)
Deferred federal income taxes	265.8	279.9	165.3
Deferred state income taxes	25.5	16.9	34.4
Total deferred income taxes	291.3	296.8	199.7
Deferred Investment Credits	(3.9)	(4.1)	(4.8)
Income Taxes from Continuing Operations	$ 261.9	$ 214.7	$ 166.7