Accumulated Other Comprehensive Loss (Changes In Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			$ 1,126.5
Retained Earnings	$ 1,185.3		1,185.3		$ 850.3
Ending balance	1,480.6		1,480.6
Amounts reclassified from accumulated other comprehensive income, tax	(5.6)	$ (6.5)	(8.6)	$ (11.0)
Actuarial (loss) gain, tax	0.1	(5.1)	0.1	(5.1)
Foreign Currency
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(7.3)	(1.7)	(5.0)	(5.1)
Other comprehensive (loss) income before reclassifications	(9.4)	(3.3)	(11.7)	0.1
Amounts reclassified from accumulated other comprehensive income (net of tax)
Actuarial (loss) gain (net of tax)
Net current-period other comprehensive (loss) income	(9.4)	(3.3)	(11.7)	0.1
Ending balance	(16.7)	(5.0)	(16.7)	(5.0)
Pension and Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(166.8)	(228.8)	(175.5)	(241.6)
Other comprehensive (loss) income before reclassifications
Amounts reclassified from accumulated other comprehensive income (net of tax)	16.1	18.8	24.8	31.6
Actuarial (loss) gain (net of tax)	(0.4)	14.9	(0.4)	14.9
Net current-period other comprehensive (loss) income	15.7	33.7	24.4	46.5
Ending balance	(151.1)	(195.1)	(151.1)	(195.1)
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(174.1)	(230.5)	(180.5)	(246.7)
Other comprehensive (loss) income before reclassifications	(9.4)	(3.3)	(11.7)	0.1
Amounts reclassified from accumulated other comprehensive income (net of tax)	16.1	18.8	24.8	31.6
Actuarial (loss) gain (net of tax)	(0.4)	14.9	(0.4)	14.9
Net current-period other comprehensive (loss) income	6.3	30.4	12.7	46.6
Ending balance	$ (167.8)	$ (200.1)	$ (167.8)	$ (200.1)

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

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