Intangible Assets and Goodwill (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Components of intangible assets
Total Proceeds From Sale Of Intangible Assets			$ 4,400
Accumulated Amortization	$ (194,777)	$ (152,448)
Intangible Assets, Gross (Excluding Goodwill)	327,165	216,714
Amortization expense for intangible assets	37,138	25,074	$ 26,618
Intangible Assets, Net	$ 132,388	$ 64,266
Minimum
Components of intangible assets
Useful Life (in years)	1 year	1 year
Maximum
Components of intangible assets
Useful Life (in years)	10 years	10 years
Favorable Contracts [Member]
Components of intangible assets
Finite-lived intangible assets	$ 3,600	$ 0
Existing technology
Components of intangible assets
Gross Carrying Amount	256,656	185,321
Accumulated Amortization	(156,577)	(127,028)
Finite-lived intangible assets	$ 100,079	$ 58,293
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	$ 65,109	$ 31,093
Accumulated Amortization	(37,900)	(25,120)
Finite-lived intangible assets	$ 27,209	$ 5,973
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-competition agreements
Components of intangible assets
Gross Carrying Amount	$ 300	$ 300
Accumulated Amortization	(300)	(300)
Finite-lived intangible assets	$ 0	$ 0
Useful Life (in years)	3 years	3 years
In Process Research and Development [Member]
Components of intangible assets
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 5,100

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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The cash inflow from disposal of asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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