Sale of Hawesville - Schedule of Major Classes of Assets and Liabilities (Details) - Discontinued Operations, Disposed of by Sale - Hawesville Facility $ in Millions	Feb. 02, 2026 USD ($)
Assets
Inventories	$ 4.1
Property, plant and equipment - net	13.5
Liabilities
Asset retirement obligations	$ 8.8

Amount classified as inventory attributable to disposal group held for sale or disposed of.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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