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Multiemployer Pension Plans - Multiemployer Pension Plan Description and Contributions (Parenthetical) (Details) | 12 Months Ended
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Dec. 31, 2023 Agreement $ / shares
Multiemployer Pension Plan Disclosure [Line Items] |
Green zone funding percentage | 80.00%
USW Plan |
Multiemployer Pension Plan Disclosure [Line Items] |
Number of collective-bargaining agreements | Agreement | 3
USW Plan | Newark and Trentwood Facilities |
Multiemployer Pension Plan Disclosure [Line Items] |
Percentage of employees covered by bargaining agreement | 87.00%
USW Plan | Newark and Trentwood Facilities | Starting in July Two Thousand Twenty |
Multiemployer Pension Plan Disclosure [Line Items] |
Monthly contributions per hour worked by each bargaining unit employee | $ 1.75
USW Plan | Richmond (Bellwood), Virginia Facility |
Multiemployer Pension Plan Disclosure [Line Items] |
Percentage of employees covered by bargaining agreement | 10.00%
Monthly contributions per hour worked by each bargaining unit employee | $ 1.50
USW Plan | Florence, Alabama Facility |
Multiemployer Pension Plan Disclosure [Line Items] |
Percentage of employees covered by bargaining agreement | 3.00%
Monthly contributions per hour worked by each bargaining unit employee | $ 1.35

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- Definition Percentage of entity's employees covered by collective-bargaining arrangement (CBA) to all entity's employees in multiemployer pension plan determined to be individually significant. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480576/715-80-50-5 + Details
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