Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 75,142	$ 62,186
Less accumulated depreciation	(42,461)	(32,422)
Property and equipment, net	32,681	29,764
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,148	7,454
Software, including internal use software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	59,718	48,731
Office equipment and furniture
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,778	4,099
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,498	$ 1,902