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Other, Net (Schedule Of Other Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Nonoperating Income [Line Items]
Interest income	$ 9.0	$ 4.3	$ 4.0
AFUDC equity	25.2	15.1	13.1
Charitable Contributions	(1.8)	(4.4)	(11.5)
Pension and Other Postretirement Non Service Cost	(24.0)	27.6	35.5
Other Nonoperating Expense	(0.4)
Miscellaneous		(0.4)	(0.3)
Total Other, net	8.0	52.2	40.8
Interest Rate Swap Settled
Other Nonoperating Income [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 0.0	$ 10.0	$ 0.0

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