Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions		12 Months Ended
		Sep. 30, 2022	Sep. 30, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		$ (136.9)	$ (191.6)
OCI before reclassifications	[1]	(77.5)	45.8
Reclassification to earnings		(1.7)	8.9
Ending Balance		(216.1)	(136.9)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		(41.8)	(47.4)
OCI before reclassifications	[1]	(89.4)	5.6
Reclassification to earnings		0.0	0.0
Ending Balance		(131.2)	(41.8)
Pension and Post-retirement Activity
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		(97.3)	(142.1)
OCI before reclassifications	[1]	(1.2)	38.1
Reclassification to earnings		5.9	6.7
Ending Balance		(92.6)	(97.3)
Hedging Activity
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		2.2	(2.1)
OCI before reclassifications	[1]	13.1	2.1
Reclassification to earnings		(7.6)	2.2
Ending Balance		$ 7.7	$ 2.2

[1] OCI is defined as other comprehensive income.