Financial Instruments (Summary Of Location And Fair Value Of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Net asset (liability)	$ (3,260)	$ (1,254)
Aluminum Futures Contracts
Derivatives, Fair Value [Line Items]
Net asset (liability)	(3,581)	1,966
Aluminum Futures Contracts \| Designated as Hedging Instrument \| Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives	48	2,085
Aluminum Futures Contracts \| Designated as Hedging Instrument \| Accrued Expenses
Derivatives, Fair Value [Line Items]
Liability derivatives: Aluminum futures contracts	(3,260)	(119)
Aluminum Futures Contracts \| Designated as Hedging Instrument \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives: Aluminum futures contracts	$ (369)	$ 0

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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