The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fourth succeeding fiscal year.

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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.

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Aggregate amount of intangible asset amortization recognized as expense during the period.

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The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

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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.

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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 aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. 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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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.

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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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The calculated weighted-average useful life of all finite-lived intangible assets.

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The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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Amortizable Intangible Assets and Goodwill (Details) (USD $)	3 Months Ended		6 Months Ended			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010	Jun. 30, 2011 Patents	Dec. 31, 2010 Patents	Jun. 30, 2011 Customer contracts and contractual relationships	Dec. 31, 2010 Customer contracts and contractual relationships	Jun. 30, 2011 Existing technology	Dec. 31, 2010 Existing technology	Jun. 30, 2011 Intellectual property	Dec. 31, 2010 Intellectual property	Jun. 30, 2011 Non-competition agreements	Dec. 31, 2010 Non-competition agreements
Components of intangible assets
Gross Carrying Amount	$ 228,117,000		$ 228,117,000		$ 68,917,000	$ 24,433,000	$ 24,433,000	$ 33,550,000	$ 4,050,000	$ 159,350,000	$ 29,950,000	$ 10,384,000	$ 10,384,000	$ 400,000	$ 100,000
Accumulated Amortization	(33,912,000)		(33,912,000)		(27,931,000)	(11,167,000)	(9,361,000)	(3,782,000)	(3,127,000)	(8,471,000)	(4,959,000)	(10,384,000)	(10,384,000)	(108,000)	(100,000)
Net Carrying Amount	194,205,000		194,205,000		40,986,000	13,266,000	15,072,000	29,768,000	923,000	150,879,000	24,991,000			292,000
Minimum useful life (in years)						3	3	1	1	3	3
Maximum useful life (in years)						10	10	10	10	7	7
Useful life (in years)												4	4	3	3
Amortization expense for intangible assets	4,000,000	1,200,000	6,000,000	2,300,000
Estimated future amortization expense of intangible assets
2011 (remaining 6 months)			16,179,000
2012			34,536,000
2013			31,471,000
2014			27,330,000
2015			26,679,000
Thereafter			58,010,000
Total			$ 194,205,000