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Curtailment of Operations - Hawesville (Details) - Curtailment Of Operations $ in Millions | 3 Months Ended
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Mar. 31, 2023 USD ($)
Restructuring Cost and Reserve [Line Items] |
Severance costs | $ 7.0
Gain (loss) on material sales | 0.7
Temporary Facility Closing, Excess Capacity |
Restructuring Cost and Reserve [Line Items] |
Excess capacity charges | $ 5.4

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