Intangibles (Net Of Amortization) And Goodwill (Schedule Of Identifiable Intangibles) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Accumulated Amortization	$ 83,676	$ 75,072
Goodwill, Gross Carrying Amount	5,132	5,091
Amortizing intangible assets and Goodwill, Gross Carrying Amount	121,723	121,598
Aggregate amortization expense	8,604	8,767
Formulas And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	91,552	91,487
Amortizing intangible assets, Accumulated Amortization	69,387	64,013
Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	16,380	16,380
Amortizing intangible assets, Accumulated Amortization	12,139	9,650
Customer Bases [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	7,050	7,040
Amortizing intangible assets, Accumulated Amortization	1,855	1,276
Trademarks And Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizing intangible assets, Gross Carrying Amount	1,609	1,600
Amortizing intangible assets, Accumulated Amortization	$ 295	$ 133

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

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ 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)(2)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Section 45

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

Reference 1: 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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

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-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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- Definition

Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

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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)

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