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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 | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 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) | $ 15 | $ 15 | $ 46 | $ 46
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) | (807) |  | (1,226) |
Cash Flow Derivative Hedges | Aluminum Futures Contracts |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Amount of pretax gain (loss) recognized in other comprehensive income (loss) | (1,176) | 757 | (111) | 1,281
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) | 300 | 231 | 1,244 | 785
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) | $ (1,353) |  | $ (3,032) |

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details
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