Intangible Assets and Goodwill (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of intangible assets
Accumulated Amortization	$ (240,480)	$ (194,777)
Finite-lived intangible assets	86,622
Indefinite-Lived Intangible Assets (Excluding Goodwill)	5,100
Intangible Assets, Gross (Excluding Goodwill)	332,202	327,165
Amortization expense for intangible assets	41,962	37,138	$ 25,074
Intangible Assets, Net	$ 91,722	$ 132,388
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	$ 1,700	$ 3,600
Existing technology
Components of intangible assets
Gross Carrying Amount	258,008	256,656
Accumulated Amortization	(191,554)	(156,577)
Finite-lived intangible assets	$ 66,454	$ 100,079
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	$ 68,794	$ 65,109
Accumulated Amortization	(48,626)	(37,900)
Finite-lived intangible assets	$ 20,168	$ 27,209
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	$ 5,100