Intangibles (Net of Amortization) and Goodwill (Schedule Of Information Related To Intangible Assets and Goodwill (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Accumulated Amortization	$ 91,237	$ 89,810
Goodwill, Gross Carrying Amount	4,722us-gaap_GoodwillGross	4,804us-gaap_GoodwillGross
Amortizing intangible assets and Goodwill, Gross Carrying Amount	106,497	106,669
Formulas And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	88,754	88,824
Amortizing intangible assets, Accumulated Amortization	83,252	82,050
Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	4,476	4,476
Amortizing intangible assets, Accumulated Amortization	3,768	3,655
Customer Bases [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	6,983	6,994
Amortizing intangible assets, Accumulated Amortization	3,409	3,336
Trademarks And Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	1,562	1,571
Amortizing intangible assets, Accumulated Amortization	$ 808	$ 769

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

+ Details

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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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