Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Net Income (Loss)		$ 6.4	$ 33.7	$ (4.0)	$ 17.3
Net derivative (losses) gains and other costs arising during the period, net of tax (benefit) expense of $(1.4); $2.9; $1.9; and $(0.9), respectively (1)	[1]	(3.6)	8.0	5.8	(2.6)
Reclassification of (gains) into net income (loss), net of tax (expense) of $(0.3); $(0.9); $(0.8); and $(1.4), respectively		(0.8)	(1.9)	(2.0)	(4.2)
Other comprehensive (loss) income		(4.4)	6.1	3.8	(6.8)
Comprehensive income (loss)		$ 2.0	$ 39.8	$ (0.2)	$ 10.5

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