CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (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	$ 78.7	$ 54.8	$ 197.7	$ 180.0
Other comprehensive income:
Reclassification adjustment transferred to Net income from cash flow hedges	0.1	0.0	0.1	0.4
Pension and other postretirement benefit costs, net of tax	0.7	0.6	1.3	0.7
Total Comprehensive Income	$ 79.5	$ 55.4	$ 199.1	$ 181.1