Property Equipment and Software, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Property, Equipment and Software, Net
Property, equipment and software at cost	$ 28,245		$ 28,245		$ 23,761
Less: accumulated depreciation	(11,460)		(11,460)		(8,091)
Property, equipment and software, net	16,785		16,785		15,670
Property, Equipment and Software, Net, Other Information
Depreciation	1,200	$ 1,100	3,500	$ 2,700
Office furniture and equipment
Property, Equipment and Software, Net
Property, equipment and software at cost	10,009		10,009		8,723
Software
Property, Equipment and Software, Net
Property, equipment and software at cost	7,323		7,323		6,004
Leasehold improvements
Property, Equipment and Software, Net
Property, equipment and software at cost	$ 10,913		$ 10,913		$ 9,034