Shareholders' Equity (Schedule of Accumulated Other Comprehensive Income (Loss) Activity (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance		$ 757.1	$ 591.8
Ending Balance		793.4	626.8
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1]	(2.2)	1.0
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	[1]	0.3	(0.8)
Amounts reclassified from accumulated other comprehensive (loss)	[1]	0.0	0.0
Net current period other comprehensive income (loss)	[1]	0.3	(0.8)
Ending Balance	[1]	(1.9)	0.2
Derivative Gain (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1],[2]	(1.1)	0.5
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	[1],[2]	(1.2)	2.2
Amounts reclassified from accumulated other comprehensive (loss)	[1],[2]	(0.3)	(1.7)
Net current period other comprehensive income (loss)	[1],[2]	(1.5)	0.5
Ending Balance	[1],[2]	(2.6)	1.0
Pension And Postretirement Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1]	(106.9)	(106.2)	[2]
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	[1]	0.0	0.0	[2]
Amounts reclassified from accumulated other comprehensive (loss)	[1]	0.6	(0.6)	[2]
Net current period other comprehensive income (loss)	[1]	0.6	(0.6)	[2]
Ending Balance	[1]	(106.3)	(106.8)	[2]
Accumulated Other Comprehensive (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	[1],[2]	(110.2)	(104.7)
Other comprehensive income (loss) before reclassifications, net of tax (expense) benefit	[1],[2]	(0.9)	1.4
Amounts reclassified from accumulated other comprehensive (loss)	[1],[2]	0.3	(2.3)
Net current period other comprehensive income (loss)	[1],[2]	(0.6)	(0.9)
Ending Balance	[1],[2]	$ (110.8)	$ (105.6)

[1] Amounts are net of tax.

[2] Amounts include our 50% share of AOCI components from our WAVE joint venture.