Intangible Assets and Goodwill (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components of intangible assets
Accumulated Amortization	$ (268,534)	$ (240,480)
Finite-lived intangible assets	58,336
Indefinite-lived Intangible Assets (Excluding Goodwill)	1,600
Intangible Assets, Gross (Excluding Goodwill)	328,470	332,202
Amortization expense for intangible assets	29,341	41,962	$ 37,138
Intangible Assets, Net	$ 59,936	$ 91,722
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	$ 900	$ 1,700
Existing technology
Components of intangible assets
Gross Carrying Amount	258,903	258,008
Accumulated Amortization	(213,824)	(191,554)
Finite-lived intangible assets	$ 45,079	$ 66,454
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	$ 67,667	$ 68,794
Accumulated Amortization	(54,410)	(48,626)
Finite-lived intangible assets	$ 13,257	$ 20,168
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)	$ 1,600	$ 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.

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