Accumulated Other Comprehensive Loss (Reclassification Out Of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-operating expenses	$ 7.8	$ 7.5
Tax benefit	16.2	8.7
Total reclassifications for the period, net of tax	(47.3)	(21.5)
Reclassification out of AOCI | Actuarial Losses Recognized
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-operating expenses	8.9	7.4
Tax benefit	(2.3)	(1.9)
Total reclassifications for the period, net of tax	$ 6.6	$ 5.5