Stock-Based Compensation and Employee Benefit Plans (Stock-based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 2,794	$ 2,974	$ 6,004	$ 6,465
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	505	521	1,040	1,292
Technology and analytics
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	657	542	1,253	1,325
Processing and servicing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	94	157	201	330
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 1,538	$ 1,754	$ 3,510	$ 3,518