Accumulated Other Comprehensive Loss (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Currency translation	$ (10.6)	$ (14.6)
Accumulated Other Comprehensive Loss	(177.9)	(152.8)
Pension Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Benefits liability	(167.2)	(138.1)
Accumulated Other Comprehensive Loss	(167.2)	(138.1)
Postretirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Benefits liability	$ (0.1)	$ (0.1)