Accumulated Other Comprehensive Loss (Reclassification Out Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-operating expenses	$ 3.1		$ 5.5		$ 5.9	$ 11.0
Tax benefit	43.6		44.1		87.5	79.4
Total reclassifications for the period, net of tax	(124.4)	$ (125.0)	(127.8)	$ (102.4)	(249.4)	(230.2)
Reclassification out of AOCI | Actuarial Losses Recognized
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-operating expenses	0.3		5.9		0.6	11.7
Tax benefit	(0.1)		(1.6)		(0.2)	(3.0)
Total reclassifications for the period, net of tax	$ 0.2		$ 4.3		$ 0.4	$ 8.7