Changes in Accumulated Other Comprehensive Loss (Classification Of Accumulated Other Comprehensive Income Reflected On Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 783.8	$ 763.8
Other comprehensive income before reclassifications	1.8
Amounts reclassified from accumulated other comprehensive loss	(1.0)
Net period other comprehensive (loss) income	0.8
Ending balance	855.2	783.8
Tax detriment	1.9	2.1
Pension and Postretirement Plan
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	9.0
Other comprehensive income before reclassifications	0.0
Amounts reclassified from accumulated other comprehensive loss	(1.0)
Net period other comprehensive (loss) income	(1.0)
Ending balance	8.0	9.0
Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(140.5)
Other comprehensive income before reclassifications	1.8
Amounts reclassified from accumulated other comprehensive loss	0.0
Net period other comprehensive (loss) income	1.8
Ending balance	(138.7)	(140.5)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(131.5)	(72.3)
Ending balance	$ (130.7)	$ (131.5)