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Financial Instruments (Narrative) (Details) lb in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) lb	Dec. 31, 2021 USD ($) lb
Derivative [Line Items]
Weight of aluminum that hedged future purchase of aluminum to meet fixed-price forward sales contract obligations, lbs | lb	20.3	14.9
Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar	$ 177.0
Amounts of unrealized after-tax gains on derivative instruments	(2.0)
Aluminum Futures Contracts
Derivative [Line Items]
Derivative, Notional Amount, Net	$ 30.7	$ 22.1

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Annual Net Costs Mismatch Translation Exposure - Real vs US Dollar

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Derivative, Notional Amount, Net

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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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.

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Nominal mass used to calculate payments on a derivative instrument.

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