CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 147.0	$ 96.2	$ 391.9	$ 165.3
Other comprehensive (loss) income:
Change in fair value of cash flow swaps	2.9	0.0	2.6	(5.1)
Income tax benefit associated with cash flow swaps	(0.7)	0.0	(0.7)	1.3
Comprehensive income	$ 149.2	$ 96.2	$ 393.8	$ 161.5