Schedule of Accumulated Other Comprehensive Income (Loss) (Details) $ in Millions	3 Months Ended
	Dec. 31, 2025 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	$ (225.6)
OCI before reclassifications	0.8
Reclassifications to earnings	(0.8)
Balance at December 31, 2022	(225.6)
Zinc contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	1.1
OCI before reclassifications	0.3
Balance at December 31, 2022	1.9
Zinc contracts \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	0.5
Foreign currency contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	(3.3)
OCI before reclassifications	(0.4)
Balance at December 31, 2022	(2.5)
Foreign currency contracts \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	1.2
Interest rate swap
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	19.3
OCI before reclassifications	0.3
Balance at December 31, 2022	16.1
Interest rate swap \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	(3.5)
Other Comprehensive Income, Foreign Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	(125.8)
OCI before reclassifications	0.8
Balance at December 31, 2022	(125.0)
Other Comprehensive Income, Foreign Currency Translation Adjustment \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	0.0
Other Comprehensive Income, Defined Benefit Plans, Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	(116.9)
OCI before reclassifications	(0.2)
Balance at December 31, 2022	(116.1)
Other Comprehensive Income, Defined Benefit Plans, Adjustment \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	$ 1.0