STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 18.3	$ (13.8)	$ 34.2	$ (5.7)
Other comprehensive (loss) income, net of tax - Note 8:
Defined benefit plans	(4.6)	0.9	(3.9)	1.8
Cash flow hedges	(2.7)	(36.5)	(4.5)	(19.4)
Other comprehensive loss, net of tax	(7.3)	(35.6)	(8.4)	(17.6)
Comprehensive income (loss)	$ 11.0	$ (49.4)	$ 25.8	$ (23.3)