Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 73,976	$ 64,732
Less: accumulated depreciation	(51,055)	(45,149)
Total	22,921	19,583
Computer Equipment And Software [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	63,684	55,293
Furniture, Equipment and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 10,292	$ 9,439