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Commitments and Contingencies (Details) $ in Millions | 1 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 31, 2018 USD ($) unilateral_administrative_order potentially_responsible_party | Nov. 27, 2015 USD ($) | Sep. 25, 2021 USD ($) property potentially_responsible_party | Oct. 31, 2008 Import_entry | Sep. 25, 2021 smelter_site | Sep. 25, 2021 USD ($) | Dec. 26, 2020 USD ($) | Jun. 30, 2018 action | Nov. 08, 2016 USD ($) | Apr. 19, 2010
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Term of guarantees |  |  | 1 year |  |  |  |  |  |  |
Payments required to be made under guarantees, maximum |  |  |  |  |  | $ 23.9 |  |  |  |
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 |  |  |  |  |  |
Deepwater Horizon Economic and Property Damage Claim |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Amount awarded to the Company |  |  |  |  |  |  | $ 22.1 |  |  |
Lead Refinery Site |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Financial guarantee |  |  |  |  |  |  |  |  | $ 1.0 |
Lead Refinery NPL Site |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Environmental reserves | $ 4.5 |  |  |  |  |  |  |  |  |
Number of UAOs | unilateral_administrative_order | 2 |  |  |  |  |  |  |  |  |
Number of PRPs | potentially_responsible_party | 4 |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |
Number of civil tort actions | action |  |  |  |  |  |  |  | 2 |  |
Reserve for settlement |  |  |  |  |  | 3.3 |  |  |  |
Non operating Properties | Southeast Kansas Sites |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of parties involved in settlement negotiations |  |  | 2 |  | 3 |  |  |  |  |
Environmental reserves |  |  |  |  |  | $ 5.6 |  |  |  |
Non operating Properties | Shasta Area Mine Sites |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Period of permit, implementation of Best Management Practices |  |  | 10 years |  |  |  |  |  |  |
Estimated remediation costs, term |  |  | 30 years |  |  |  |  |  |  |
Non operating Properties | Lead Refinery Site |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of parties involved in settlement negotiations | potentially_responsible_party |  |  | 2 |  |  |  |  |  |  |
Estimated remediation costs, term |  |  | 16 years |  |  |  |  |  |  |
Amount other PRPs will pay to fund cleanup |  |  | $ 26.0 |  |  |  |  |  |  |
Number of surrounding properties | property |  |  | 300 |  |  |  |  |  |  |
Non operating Properties | Minimum | Shasta Area Mine Sites |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  | $ 13.9 |  |  |  |  |  |  |
Non operating Properties | Minimum | Lead Refinery Site |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  | 1.7 |  |  |  |  |  |  |
Non operating Properties | Maximum | Shasta Area Mine Sites |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  | 18.0 |  |  |  |  |  |  |
Non operating Properties | Maximum | Lead Refinery Site |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  | $ 2.4 |  |  |  |  |  |  |
Operating Properties | Mueller Copper Tube Products, Inc. |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs, term |  |  | 5 years |  |  |  |  |  |  |
Operating Properties | Minimum | Mueller Copper Tube Products, Inc. |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  | $ 0.9 |  |  |  |  |  |  |
Operating Properties | Maximum | Mueller Copper Tube Products, Inc. |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated remediation costs |  |  | $ 1.1 |  |  |  |  |  |  |

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