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Derivative Financial Instruments (Schedule Of Pretax Effect On Net Income (Loss) And Other Comprehensive Income (Loss) Of Derivative Instruments Classified As Cash Flow Hedges) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Foreign Currency Forwards And Options [Member] | Cost Of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) reclassified from accumulated other comprehensive income (loss) to net income (effective portion)	$ 17	$ 15
Foreign Currency Forwards And Options [Member] | Selling, General and Administrative Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) reclassified from accumulated other comprehensive income (loss) to net income (effective portion)	(2)	(794)
Cash Flow Derivative Hedges | Aluminum Futures Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) recognized in other comprehensive income (loss)	1,515	(1,594)
Cash Flow Derivative Hedges | Aluminum Futures Contracts | Cost Of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) reclassified from accumulated other comprehensive income (loss) to net income (effective portion)	640	(640)
Cash Flow Derivative Hedges | Foreign Currency Forwards And Options
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) recognized in other comprehensive income (loss)	0	0
Cash Flow Derivative Hedges | Foreign Currency Forwards And Options | Selling, General and Administrative Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) recognized in other comprehensive income (loss)	$ (1,283)	$ (4,824)

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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