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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		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
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)	$ 16	$ 16	$ 31	$ 31
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)	(369)	(378)	(560)
Cash Flow Derivative Hedges | Aluminum Futures Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) recognized in other comprehensive income (loss)	(1,192)	1,457	(1,438)	1,065
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)	(606)	712	(1,223)	944
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		$ 0
Cash Flow Derivative Hedges | Foreign Currency Forwards And Options | Cost Of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pretax gain (loss) recognized in other comprehensive income (loss)			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)	$ 719	$ (1,849)	$ (97)

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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.

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
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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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