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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, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 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 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) | (378) |  | (419) |
Cash Flow Derivative Hedges | Aluminum Futures Contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of pretax gain (loss) recognized in other comprehensive income (loss) | 1,457 | (322) | 1,065 | 524
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) | 712 | 321 | 944 | 554
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) | $ (1,849) |  | $ (1,679) |

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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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