Intangibles (Net of Amortization) and Goodwill (Schedule Of Information Related To Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Accumulated Amortization	$ 10,657	$ 95,514
Goodwill, Gross Carrying Amount	4,605	4,656
Amortizing intangible assets and Goodwill, Gross Carrying Amount	20,419	106,421
Formulas And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	2,823	88,763
Amortizing intangible assets, Accumulated Amortization	1,771	86,861
Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	4,476	4,476
Amortizing intangible assets, Accumulated Amortization	4,215	4,103
Customer Bases [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	6,971	6,977
Amortizing intangible assets, Accumulated Amortization	3,711	3,627
Trademarks And Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	1,544	1,549
Amortizing intangible assets, Accumulated Amortization	$ 960	$ 923

Gross amount, as of the balance sheet date, of finite lived intangible assets and of goodwill.

No definition available.

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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=26713463&loc=d3e16323-109275

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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a,h)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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