Schedule of Accumulated Other Comprehensive Income (Loss) (Details) $ in Millions	6 Months Ended
	Mar. 31, 2024 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2023	$ (137.7)
OCI before reclassifications	(10.8)
Reclassifications to earnings	(7.3)
Balance at December 31, 2022	(155.8)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2023	(89.7)
OCI before reclassifications	(3.6)
Reclassifications to earnings	0.0
Balance at December 31, 2022	(93.3)
Pension Activity
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2023	(110.3)
OCI before reclassifications	(0.7)
Reclassifications to earnings	1.1
Balance at December 31, 2022	(109.9)
Foreign Currency Contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2023	2.1
OCI before reclassifications	(1.6)
Reclassifications to earnings	(0.4)
Balance at December 31, 2022	0.1
Zinc contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2023	(0.5)
OCI before reclassifications	(3.9)
Reclassifications to earnings	4.0
Balance at December 31, 2022	(0.4)
Interest Rate Contracts | Foreign Currency Contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2023	60.7
OCI before reclassifications	(1.0)
Reclassifications to earnings	(12.0)
Balance at December 31, 2022	$ 47.7