Stock-based Awards (Details 3 - Stock comp by FSLI) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Stock-based Compensation Cost
Stock-based compensation expense	$ 10,247	$ 9,908	$ 28,316	$ 22,661
Amount capitalized to internal software use	551	443	1,358	993
Total stock-based compensation cost	10,798	10,351	29,674	23,654
Cost of revenue
Stock-based Compensation Cost
Stock-based compensation expense	469	339	1,210	775
Sales and marketing
Stock-based Compensation Cost
Stock-based compensation expense	3,852	3,358	10,522	7,263
Technology and development
Stock-based Compensation Cost
Stock-based compensation expense	2,829	2,598	7,880	5,496
General and administrative
Stock-based Compensation Cost
Stock-based compensation expense	$ 3,097	$ 3,613	$ 8,704	$ 9,127

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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