Pension And Other Postretirement Benefits (Schedule Of Net Periodic Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Total selling, general, and administrative expenses			$ 1,098.9	$ 1,159.9	$ 1,125.0
Total non-operating expenses			58.5	23.7	30.6
Pension Benefits
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost			29.2	25.6	28.6
Total selling, general, and administrative expenses			29.2	25.6	28.6
Interest cost			26.7	30.0	27.3
Expected return on plan assets			(32.8)	(34.1)	(31.9)
Net actuarial loss			30.2	19.1	26.5
Prior service cost (gain)					0.3
Settlement charge			27.7
Total non-operating expenses			51.8	15.0	22.2
Net periodic benefit cost			$ 81.0	$ 40.6	$ 50.8
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	2.72%	3.38%		4.31%	3.67%
Expected return on plan assets			5.50%	5.75%	5.75%
Rate of compensation increase			4.24%	4.36%	4.49%
Postretirement Benefits
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost			$ 2.1	$ 2.0	$ 2.3
Total selling, general, and administrative expenses			2.1	2.0	2.3
Interest cost			2.4	2.9	2.6
Net actuarial loss				0.3	0.9
Prior service cost (gain)			0.7		(2.0)
Total non-operating expenses			3.1	3.2	1.5
Net periodic benefit cost			$ 5.2	$ 5.2	$ 3.8
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate			3.19%	4.16%	3.44%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Net Periodic Benefit Cost			5.00%	5.00%	5.50%
Defined Benefit Plan Ultimate Health Care Cost Trend Rate For Benefit Obligation, Net Periodic Benefit Cost					5.00%