Employee Benefit Plans (Schedule of Total Stock-Based Compensation Expense Resulting from Stock Options, RSUs, and the ESPP) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 29,137	$ 26,461	$ 18,969
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	2,843	2,435	1,406
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	6,532	4,283	2,968
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	9,069	8,267	5,481
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 10,693	$ 11,476	$ 9,114