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Goodwill And Other Intangible Assets (Schedule Of Intangible Assets With Determinable Useful Lives By Major Category) (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
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Goodwill [Line Items] |  |
Gross Carrying Amount | $ 142,300 | $ 142,300
Accumulated Amortization & Impairment | (36,703) | (33,414)
Net Carrying Amount | 105,597 | 108,886
Trade Name |  |
Goodwill [Line Items] |  |
Gross Carrying Amount | 22,500 | 22,500
Accumulated Amortization & Impairment | (6,071) | (5,512)
Net Carrying Amount | 16,429 | 16,988
Technological Know-How |  |
Goodwill [Line Items] |  |
Gross Carrying Amount | 55,300 | 55,300
Accumulated Amortization & Impairment | (18,884) | (17,265)
Net Carrying Amount | 36,416 | 38,035
Customer-Related Intangible |  |
Goodwill [Line Items] |  |
Gross Carrying Amount | 64,500 | 64,500
Accumulated Amortization & Impairment | (11,748) | (10,637)
Net Carrying Amount | $ 52,752 | $ 53,863

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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