Components of Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 28.5	$ 32.2	$ 87.7	$ 111.6
Other comprehensive (loss) income
Derivative contracts (decrease) increase	(5.7)	2.1	(4.5)	0.6
Total comprehensive income	$ 22.8	$ 34.3	$ 83.2	$ 112.2