Shareholders' Equity (Schedule of Accumulated Other Comprehensive (Loss) Activity) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		$ 626.8	$ 544.8	$ 591.8	$ 535.0
Ending Balance		669.0	566.7	669.0	566.7
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1]	0.2	0.4	1.0	0.5
Other comprehensive (loss) income before reclassifications, net of tax benefit (expense)	[1]	(0.4)	0.7	(1.2)	0.6
Amounts reclassified from accumulated other comprehensive (loss)	[1]	0.0	0.0	0.0	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	[1]	(0.4)	0.7	(1.2)	0.6
Ending Balance	[1]	(0.2)	1.1	(0.2)	1.1
Derivative (Loss) Gain [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1]	1.0	7.3	0.5	9.5
Other comprehensive (loss) income before reclassifications, net of tax benefit (expense)	[1]	1.1	2.1	3.3	1.8
Amounts reclassified from accumulated other comprehensive (loss)	[1]	(0.9)	(2.3)	(2.6)	(4.2)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	[1]	0.2	(0.2)	0.7	(2.4)
Ending Balance	[1]	1.2	7.1	1.2	7.1
Pension And Postretirement Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1]	(106.8)	(109.9)	(106.2)	(110.1)
Other comprehensive (loss) income before reclassifications, net of tax benefit (expense)	[1]	0.0	(0.1)	0.0	0.3
Amounts reclassified from accumulated other comprehensive (loss)	[1]	(0.7)	0.0	(1.3)	(0.2)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	[1]	(0.7)	(0.1)	(1.3)	0.1
Ending Balance	[1]	(107.5)	(110.0)	(107.5)	(110.0)
Accumulated Other Comprehensive (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1]	(105.6)	(102.2)	(104.7)	(100.1)
Other comprehensive (loss) income before reclassifications, net of tax benefit (expense)	[1]	0.7	2.7	2.1	2.7
Amounts reclassified from accumulated other comprehensive (loss)	[1]	(1.6)	(2.3)	(3.9)	(4.4)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	[1]	(0.9)	0.4	(1.8)	(1.7)
Ending Balance	[1]	$ (106.5)	$ (101.8)	$ (106.5)	$ (101.8)

[1] (1) Amounts are net of tax.