Derivative Financial Instruments (Effect Of Fair Value Hedges On Income Statement) (Details) - Fixed Rate Debt [Member] - Interest Rate Swaps [Member] - Interest Expense [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Hedge Gain (Loss) Recognized	$ 0.0	$ 2.0	$ (0.2)	$ 6.6
Hedged Item Gain (Loss) Recognized	$ 0.0	$ (2.0)	$ 0.2	$ (6.6)