Goodwill And Related Intangible Assets (Schedule Of Acquired Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Finite-lived	$ 76,478	$ 52,650
Total acquired intangible assets, Gross Carrying Amount	123,241	88,053
Accumulated Amortization	26,250	21,752
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Finite-lived	48,336	42,469
Accumulated Amortization	19,594	16,832
Estimated Life, Minimum	5
Estimated Life, Maximum	16
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Finite-lived	2,857	2,656
Accumulated Amortization	2,202	1,921
Estimated Life, Minimum	5
Estimated Life, Maximum	10
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Finite-lived	1,200
Accumulated Amortization	400
Estimated Life, Minimum	1
Estimated Life, Maximum	2
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Indefinite-lived	46,763	35,403
Gross Carrying Amount, Finite-lived	1,968	1,968
Accumulated Amortization	881	760
Estimated Life, Minimum	2
Estimated Life, Maximum	15
Unpatented Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Finite-lived	22,117	5,557
Accumulated Amortization	$ 3,173	$ 2,239
Estimated Life, Minimum	5
Estimated Life, Maximum	20

Acquired Intangible Assets, Total.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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-Publisher FASB

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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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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.

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The maximum useful life 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 Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 35

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6904245&loc=d3e15217-109273

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The minimum useful life 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.

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- Definition

Carrying amount of intangible assets, excluding goodwill, which have a projected indefinite period of benefit (hence are not amortized), allocated to the reportable segment. These assets, acquired either individually or as part of a group of assets, in either an asset acquisition or business combination, are assessed at least annually for impairment. Examples may include trade secrets, contractual rights, trade names, and licensing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 350

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-Paragraph 2

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