Accumulated Other Comprehensive Loss (Changes In Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			$ 892.9
Ending balance	$ 948.6		948.6
Amounts reclassified from accumulated other comprehensive loss, tax	(2.0)	$ (1.2)	(3.9)	$ (2.5)
Foreign Currency
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(16.6)	(10.4)	(7.7)	(12.4)
Other comprehensive (loss) income before reclassifications	3.9	2.0	(5.0)	4.0
Amounts reclassified from accumulated other comprehensive income (net of tax $(2.0), $(1.2), $(3.9) and $(2.5))
Net current-period other comprehensive (loss) income	3.9	2.0	(5.0)	4.0
Ending balance	(12.7)	(8.4)	(12.7)	(8.4)
Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(237.4)	(224.2)	(242.9)	(227.9)
Other comprehensive (loss) income before reclassifications
Amounts reclassified from accumulated other comprehensive income (net of tax $(2.0), $(1.2), $(3.9) and $(2.5))	5.7	3.5	11.2	7.2
Net current-period other comprehensive (loss) income	5.7	3.5	11.2	7.2
Ending balance	(231.7)	(220.7)	(231.7)	(220.7)
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(254.0)	(234.6)	(250.6)	(240.3)
Other comprehensive (loss) income before reclassifications	3.9	2.0	(5.0)	4.0
Amounts reclassified from accumulated other comprehensive income (net of tax $(2.0), $(1.2), $(3.9) and $(2.5))	5.7	3.5	11.2	7.2
Net current-period other comprehensive (loss) income	9.6	5.5	6.2	11.2
Ending balance	$ (244.4)	$ (229.1)	$ (244.4)	$ (229.1)

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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