Goodwill And Other Intangible Assets (Schedule Of Intangible Assets With Determinable Useful Lives By Major Category) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Goodwill [Line Items]
Gross Carrying Amount	$ 142,300	$ 142,300
Accumulated Amortization & Impairment	(26,747)	(19,809)
Net Carrying Amount	115,553	122,491
Trade Name
Goodwill [Line Items]
Gross Carrying Amount	22,500	22,500
Accumulated Amortization & Impairment	(4,386)	(3,235)
Net Carrying Amount	18,114	19,265
Technological Know-How
Goodwill [Line Items]
Gross Carrying Amount	55,300	55,300
Accumulated Amortization & Impairment	(13,949)	(10,397)
Net Carrying Amount	41,351	44,903
Customer-Related Intangible
Goodwill [Line Items]
Gross Carrying Amount	64,500	64,500
Accumulated Amortization & Impairment	(8,412)	(6,177)
Net Carrying Amount	$ 56,088	$ 58,323

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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