Intangible Asset and Goodwill (Details 3) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Components of intangible assets
Gross Carrying Amount	$ 216,714,000		216,714,000
Accumulated Amortization	(133,665,000)		(127,343,000)
Net Carrying Amount	83,049,000us-gaap_FiniteLivedIntangibleAssetsNet		89,371,000us-gaap_FiniteLivedIntangibleAssetsNet
Amortization expense for intangible assets	6,322,000us-gaap_AmortizationOfIntangibleAssets	6,797,000us-gaap_AmortizationOfIntangibleAssets
Existing technology
Components of intangible assets
Gross Carrying Amount	185,321,000		185,321,000
Accumulated Amortization	(110,130,000)		(104,426,000)
Net Carrying Amount	75,191,000		80,895,000
Existing technology \| Minimum
Components of intangible assets
Useful Life (in years)	3 years		3 years
Existing technology \| Maximum
Components of intangible assets
Useful Life (in years)	10 years		10 years
Customer contracts and contractual relationships
Components of intangible assets
Gross Carrying Amount	31,093,000		31,093,000
Accumulated Amortization	(23,235,000)		(22,617,000)
Net Carrying Amount	7,858,000		8,476,000
Customer contracts and contractual relationships \| Minimum
Components of intangible assets
Useful Life (in years)	1 year		1 year
Customer contracts and contractual relationships \| Maximum
Components of intangible assets
Useful Life (in years)	10 years		10 years
Non-compete agreements
Components of intangible assets
Useful Life (in years)	3 years		3 years
Gross Carrying Amount	300,000		300,000
Accumulated Amortization	(300,000)		(300,000)
Net Carrying Amount	0		0
Favorable contracts
Components of intangible assets
Net Carrying Amount	100,000		100,000
Cash received related to favorable contracts	$ 0	$ 900,000

Represents the cash received on account of intangible assets.

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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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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 after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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