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Commitments and Contingencies (Details) $ in Millions | 1 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 31, 2024 USD ($) | Mar. 31, 2022 potentially_responsible_party | Feb. 28, 2022 USD ($) smelter_site ft | Jan. 31, 2018 USD ($) potentially_responsible_party unilateralAdministrativeOrder | Nov. 27, 2015 USD ($) | Aug. 31, 2015 mining_site | Sep. 27, 2025 USD ($) property smelter_site potentially_responsible_party | Oct. 31, 2008 import_entry | Dec. 25, 2021 USD ($) | 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 |  |  |  |  |  |  | $ 28.2 |  |  |  |  |
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%
Payment for interest and duties |  |  |  |  | $ 3.0 |  |  |  |  |  |  |
Number of import entries | import_entry |  |  |  |  |  |  |  | 795 |  |  |  |
Southeast Kansas Sites |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Accrual for environmental loss contingencies, gross |  |  | $ 5.6 |  |  |  |  |  |  |  |  |
Geographic boundary of sites | ft |  |  | 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 |  |  |  |  |
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 |  |  |  |  |  |  | $ 13.2 |  |  |  |  |
Shasta Area Mine Sites | Non operating Properties | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  |  |  |  |  | $ 14.9 |  |  |  |  |
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 |  |  |  |  |
Number of surrounding properties | property |  |  |  |  |  |  | 300 |  |  |  |  |
Estimated remediation costs, term |  |  |  |  |  |  | 12 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 |  |  |  |  |  |  | 2.3 |  |  |  |  |
Lead Refinery Site | Non operating Properties | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  |  |  |  |  | 2.7 |  |  |  |  |
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 mining sites | mining_site |  |  |  |  |  | 48 |  |  |  |  |  |
Mueller Copper Tube Products, Inc. | Operating Properties | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  |  |  |  |  | $ 0.3 |  |  |  |  |

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