Property and Equipment (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 32,513	$ 31,154
Accumulated depreciation	(28,091)	(26,933)
Property and equipment—net	4,422	4,221
Information technology
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 26,938	25,588
Information technology | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Information technology | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,568	4,568
Leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,007	$ 998
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years