Shareholders' Equity (Schedule Of Accumulated Other Comprehensive Income Activity) (Parenthetical) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive income (loss) before reclassifications, tax (benefit) expense	$ 3.8	$ 11.9
Derivative Gain (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive income (loss) before reclassifications, tax (benefit) expense	5.2	0.6
Pension And Postretirement Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive income (loss) before reclassifications, tax (benefit) expense	$ (1.4)	$ 11.3