STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 24.6	$ 15.9
Other comprehensive (loss) income, net of tax - Note 8:
Defined benefit plans	(0.5)	0.7
Cash flow hedges	(1.6)	(1.8)
Other comprehensive loss, net of tax	(2.1)	(1.1)
Comprehensive income	$ 22.5	$ 14.8