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Commitments and Contingencies (Details) $ in Millions		1 Months Ended							6 Months Ended	12 Months Ended
Commitments and Contingencies (Details) $ in Millions	Jan. 07, 2025 potentially_responsible_party	Jul. 31, 2024 USD ($)	Aug. 31, 2023 property	Mar. 31, 2022 potentially_responsible_party	Feb. 28, 2022 USD ($) smelter_site foot	Jan. 31, 2018 USD ($) potentially_responsible_party unilateralAdministrativeOrder	Aug. 31, 2015 mining_site	Sep. 30, 2014 USD ($) property potentially_responsible_party	Jun. 27, 2026 USD ($) potentially_responsible_party smelter_site property	Oct. 31, 2008 import_entry	Apr. 08, 2026 USD ($)	Dec. 25, 2021 USD ($)	Dec. 31, 2018 potentially_responsible_party	Nov. 08, 2016 USD ($)	Apr. 19, 2010
Loss Contingencies [Line Items]
Term of guarantees									1 year
Payments required to be made under guarantees, maximum									$ 27.5
United States Department of Commerce Antidumping Review
Loss Contingencies [Line Items]
Assignment of antidumping duty rate on U.S. imports by Company subsidiaries (as a percent)															48.33%
Number of import entries \| import_entry										795
United States Department of Commerce Antidumping Review \| Southland Pipe Nipples Co., Inc.
Loss Contingencies [Line Items]
Duties and interest sought from third party after protests denied											$ 5.1
Southeast Kansas Sites
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies, gross					$ 5.6
Geographic boundary of sites \| foot					50
Southeast Kansas Sites \| Non operating Properties
Loss Contingencies [Line Items]
Number of former smelter sites \| smelter_site					3				3
Number of parties involved in settlement negotiations \| potentially_responsible_party													2
Southeast Kansas Sites - Lanyon \| Operating Properties
Loss Contingencies [Line Items]
Number of properties in remediation \| property									1,371
EPA review, term			5 years
Number of surrounding properties \| property			300
Shasta Area Mine Sites \| Non operating Properties
Loss Contingencies [Line Items]
Period of permit, implementation of best management practices									10 years
Estimated remediation costs, term									30 years
Shasta Area Mine Sites \| Non operating Properties \| Minimum
Loss Contingencies [Line Items]
Estimated remediation costs									$ 13.7
Shasta Area Mine Sites \| Non operating Properties \| Maximum
Loss Contingencies [Line Items]
Estimated remediation costs									$ 14.8
Lead Refinery Site
Loss Contingencies [Line Items]
Financial guarantee														$ 1.0
Lead Refinery Site \| Non operating Properties
Loss Contingencies [Line Items]
Number of parties involved in settlement negotiations \| potentially_responsible_party								2	2
Number of surrounding properties \| property								300
Estimated remediation costs, term									11 years
Amount other PRPs will pay to fund cleanup								$ 26.0
Lead Refinery Site \| Non operating Properties \| Minimum
Loss Contingencies [Line Items]
Estimated remediation costs									$ 1.9
Lead Refinery Site \| Non operating Properties \| Maximum
Loss Contingencies [Line Items]
Estimated remediation costs									2.0
Lead Refinery NPL Site
Loss Contingencies [Line Items]
Number of UAOs \| unilateralAdministrativeOrder						2
Number of PRPs \| potentially_responsible_party				4		4
Environmental reserves						$ 4.5
Site contingency, total costs						25.0
Site contingency, amount agreed upon to pay PRPs for past costs						2.0
Site contingency, additional reimbursement of past costs						$ 0.7
Contingency charge									$ 7.6
Reserve for settlement												$ 3.3
Litigation settlement		$ 0.1
Bonita Peak Mining District
Loss Contingencies [Line Items]
Number of PRPs \| potentially_responsible_party	3
Number of mining sites \| mining_site							48
Mueller Copper Tube Products, Inc. \| Operating Properties
Loss Contingencies [Line Items]
Estimated remediation costs, term									5 years
Mueller Copper Tube Products, Inc. \| Operating Properties \| Minimum
Loss Contingencies [Line Items]
Estimated remediation costs									$ 0.9
Mueller Copper Tube Products, Inc. \| Operating Properties \| Maximum
Loss Contingencies [Line Items]
Estimated remediation costs									$ 1.1