STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 46.8	$ 47.2	$ (29.6)
Other comprehensive income (loss), net of tax-Note 11:
Defined benefit plans	8.1	8.2	24.2
Cash flow hedges	(0.7)	1.7	(17.3)
Other comprehensive (loss) income, net of tax	7.4	9.9	6.9
Comprehensive income (loss)	$ 54.2	$ 57.1	$ (22.7)