Commitments and Contingencies - Legal Matters (Details)	1 Months Ended		3 Months Ended	9 Months Ended
	Jul. 31, 2016 USD ($) installment	Nov. 30, 2015 patent company	Sep. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)
Patent Infringement Case Against Limelight [Member]
Loss Contingencies [Line Items]
License agreement payment	$ 54,000,000
License agreement, number of installments | installment	12
License agreement term	3 years
Proceeds from legal settlements			$ 4,500,000	$ 13,500,000
Patent Infringement Case Against Limelight [Member] | Interest Income [Member]
Loss Contingencies [Line Items]
Litigation settlement income			400,000	1,200,000
Patent Infringement Case Against Limelight [Member] | General and administrative
Loss Contingencies [Line Items]
Litigation settlement income			4,100,000	12,300,000
Patent Infringement Case Against Limelight [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Patents allegedly infringed | patent		5
Patent Infringement Case Against Company and XO [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Number of companies in case | company		2
Patents allegedly infringed | patent		6
Provision for contingency			$ 0	$ 0