Accumulated Other Comprehensive Loss (Reclassification Out Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-operating expenses, net	$ 0.3			$ 0.8			$ 3.2	$ 2.9
Tax benefit	40.4			40.0			123.2	114.5
Total reclassifications for the period, net of tax	(119.6)	$ (138.4)	$ (101.1)	(110.5)	$ (110.6)	$ (105.5)	(359.1)	(326.6)
Amortization Of Pension And Other Postretirement Benefits Items [Member] | Actuarial Losses Recognized [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-operating expenses, net	2.5			1.9			7.4	5.7
Tax benefit	(0.7)			(0.5)			(1.9)	(1.5)
Total reclassifications for the period, net of tax	$ 1.8			$ 1.4			$ 5.5	$ 4.2