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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
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Mar. 31, 2018 | Mar. 31, 2017
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 (loss) (effective portion) | $ 15 | $ 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 (loss) (effective portion) | (41) |
Cash Flow Derivative Hedges | Aluminum Futures Contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of pretax gain (loss) recognized in other comprehensive income (loss) | (392) | 846
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 (loss) (effective portion) | 232 | 233
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
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) | $ 170 |

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- Definition 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + Details
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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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