Derivative Financial Instruments (Summary Of Location And Fair Value Of Derivative Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 2,276	$ 811
Aluminum Futures Contracts
Derivatives, Fair Value [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	(2,961)	(3,581)
Derivatives Designated As Hedging Instruments [Member] \| Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives: Fair Value	0	3
Derivatives Designated As Hedging Instruments [Member] \| Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	1,854	781
Derivatives Designated As Hedging Instruments [Member] \| Other Noncurrent Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	422	33
Derivatives Designated As Hedging Instruments [Member] \| Aluminum Futures Contracts \| Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives: Fair Value	(2,694)	(3,260)
Derivatives Designated As Hedging Instruments [Member] \| Aluminum Futures Contracts \| Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	48
Derivatives Designated As Hedging Instruments [Member] \| Aluminum Futures Contracts \| Other non-current liabilities
Derivatives, Fair Value [Line Items]
Liability derivatives: Fair Value	$ (267)	$ (369)

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-SubTopic 10
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480463/815-10-45-5

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483444/210-20-55-22

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Name Accounting Standards Codification
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-4D

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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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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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No definition available.

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