Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 11,307	$ 14,003
Accumulated depreciation and amortization	(10,148)	(11,800)
Property and equipment, net	$ 1,159	2,203
Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Network equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 7,787	10,588
Network equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Network equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 3,165	3,059
Computer equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Computer equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	4 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 87	87
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 268	$ 269
Office furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Office furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	10 years