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Business, Product and Geographical Area Information and Concentration of Risk - Schedule of Export Sales and Primary Aluminum Supply from Major Suppliers (Details) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Export Sales | Geographic Concentration Risk | Supplier |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 10.00% | 10.00% | 14.00%
Aluminum | Supplier Concentration Risk | Top Five Major Suppliers |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 78.00% | 72.00% | 74.00%
Aluminum | Supplier Concentration Risk | Largest Supplier |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 47.00% | 21.00% | 22.00%
Aluminum | Supplier Concentration Risk | Second and Third Largest Suppliers |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk, percentage | 20.00% | 32.00% | 32.00%

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