Schedule of Accumulated Other Comprehensive Income (Loss) (Details) $ in Millions	9 Months Ended
	Jun. 30, 2026 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	$ (225.6)
OCI before reclassifications	20.5
Reclassifications to earnings	22.4
Balance at December 31, 2022	(182.7)
Zinc contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	1.1
OCI before reclassifications	2.3
Balance at December 31, 2022	2.6
Zinc contracts \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	(0.8)
Foreign currency contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	(3.3)
OCI before reclassifications	0.2
Balance at December 31, 2022	0.2
Foreign currency contracts \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	3.3
Interest rate swap
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at September 30, 2025	19.3
OCI before reclassifications	4.3
Balance at December 31, 2022	14.8
Interest rate swap \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	(8.8)
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	15.5
Balance at December 31, 2022	(110.3)
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	(1.8)
Balance at December 31, 2022	(90.0)
Other Comprehensive Income, Defined Benefit Plans, Adjustment \| Amount Reclassified from AOCI
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassifications to earnings	$ 28.7