Stock-Based Compensation and Employee Benefit Plans (Stock-based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 3,248	$ 2,794	$ 6,331	$ 6,004
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	474	505	1,033	1,040
Technology and analytics
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	889	657	1,717	1,253
Processing and servicing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	49	94	139	201
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 1,836	$ 1,538	$ 3,442	$ 3,510