Intangibles (Net of Amortization) and Goodwill (Schedule Of Information Related To Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Accumulated Amortization	$ 86,186	$ 84,322
Goodwill, Gross Carrying Amount	4,879	5,002
Amortizing intangible assets and Goodwill, Gross Carrying Amount	114,564	114,864
Formulas And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	91,526	91,662
Amortizing intangible assets, Accumulated Amortization	76,106	74,762
Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	9,593	9,593
Amortizing intangible assets, Accumulated Amortization	7,079	6,734
Customer Bases [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	7,006	7,021
Amortizing intangible assets, Accumulated Amortization	2,509	2,400
Trademarks And Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	1,560	1,586
Amortizing intangible assets, Accumulated Amortization	$ 492	$ 426

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=7658586&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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

Gross amount, as of the balance sheet date, of the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable), in excess of the fair value of net assets acquired in one or more business combination transactions.

+ 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=14024403&loc=d3e13816-109267

+ Details

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