Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (437.5)	$ 513.4	$ 388.6
Other comprehensive income (loss):
Net foreign currency translation adjustment	(27.2)	4.5	11.3
Net unrealized gain (loss) on derivative instruments, net of tax	29.9	19.8	(14.6)
Reclassification of net unrealized (gains) losses on derivative instruments to net income, net of tax	(6.8)	5.4	7.5
Net unrealized loss on securities, net of tax	(77.4)	(2.3)	0.0
Net unrealized gain (loss) in pension and other post-retirement benefits, net of tax	(5.4)	5.1	(9.6)
Pension and other post-retirement benefit adjustments, net of tax	8.7	0.3	0.2
Total other comprehensive income (loss)	(78.2)	32.8	(5.2)
Comprehensive income (loss)	(515.7)	546.2	383.4
Comprehensive income attributable to noncontrolling interest	0.0	(0.9)	(1.2)
Comprehensive income (loss) attributable to controlling interest	$ (515.7)	$ 545.3	$ 382.2