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Fair Value Measurements - Nonrecurring Fair Value Measurements (Details) - Fair Value, Nonrecurring [Member] - Hawesville Asset Group $ in Millions | Sep. 30, 2022 USD ($)
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Asset group fair value | $ 15.0
Discounted cash flow [Member] | Level 3 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Asset group fair value | $ 15.0

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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