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Pensions and Postretirement Benefits Other than Pensions (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Company contributions			$ 51.8	$ 37.1
Pension Costs [Member]
Defined Benefit Plan, Benefit Obligation, Divestiture			488.7
Defined Benefit Plan, Plan Assets, Divestiture			351.3
Actuarial gain (loss)	$ (10.3)	$ (13.3)	(21.6)	(26.7)
Pension Plan, Defined Benefit [Member]
Expected future employer contributions in 2017	98.0		98.0
Postretirement Benefit Costs [Member]
Defined Benefit Plan, Benefit Obligation, Divestiture			29.8
Actuarial gain (loss)	$ 1.0	$ 1.6	2.1	$ 3.2
Reverse Morris Trust Transaction [Member]
Company contributions			24.4
Accumulated Defined Benefit Plans Adjustment [Member] \| Pension Costs [Member]
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent			114.2
Accumulated Defined Benefit Plans Adjustment [Member] \| Postretirement Benefit Costs [Member]
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent			$ 4.1