Consolidated Statements of Comprehensive Income - USD ($) $ in Millions		12 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net Income (Loss)		$ 66.4	$ (7.7)	$ 14.0
Net derivative (losses) gains and other costs arising during the period, net of tax expense of $(3.7), $9.5; and $1.7, respectively	[1]	(10.4)	26.5	4.2
Reclassification of (gains) into net income (loss), net of tax (expense) of $(2.9); $(3.8); and $(0.3), respectively		(8.2)	(11.4)	(0.7)
Other comprehensive (loss) income		(18.6)	15.1	3.5
Comprehensive income		$ 47.8	$ 7.4	$ 17.5

[1] Other costs include the effects of foreign currency translation adjustments which were immaterial during the periods presented.