Acquisitions Acquisitions - Intangible Assets Acquired (Details) - USD ($) $ in Thousands	May. 18, 2015	Jan. 08, 2015
Sanbolic, Inc. [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 45,300
Sanbolic, Inc. [Member] | Core and Product Technologies [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		43,800
Sanbolic, Inc. [Member] | Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 1,500
Useful life of intangible assets acquired		2 years
Sanbolic, Inc. [Member] | Telecommunication Carrier Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 0
Sanbolic, Inc. [Member] | Trade Name [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 0
Grasshopper Group, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 71,400
Grasshopper Group, LLC [Member] | Core and Product Technologies [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 25,000
Useful life of intangible assets acquired	7 years
Grasshopper Group, LLC [Member] | Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 37,900
Useful life of intangible assets acquired	5 years
Grasshopper Group, LLC [Member] | Telecommunication Carrier Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 7,900
Useful life of intangible assets acquired	2 years
Grasshopper Group, LLC [Member] | Trade Name [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 600
Useful life of intangible assets acquired	2 years
Minimum [Member] | Sanbolic, Inc. [Member] | Core and Product Technologies [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets acquired		5 years
Maximum [Member] | Sanbolic, Inc. [Member] | Core and Product Technologies [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets acquired		6 years