Stock-based Awards (Details 3 - Stock comp by FSLI) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Stock-based Compensation Cost
Stock-based compensation expense	$ 15,556	$ 8,972	$ 24,191	$ 18,069
Amount capitalized to internal software use	505	473	978	807
Total stock-based compensation cost	16,061	9,445	25,169	18,876
Certain executive-level employees
Stock-based Compensation Cost
Termination benefits	7,200		7,200
Cost of revenue
Stock-based Compensation Cost
Stock-based compensation expense	553	443	1,052	741
Sales and marketing
Stock-based Compensation Cost
Stock-based compensation expense	4,716	3,543	8,188	6,670
Technology and development
Stock-based Compensation Cost
Stock-based compensation expense	3,463	2,698	5,409	5,051
General and administrative
Stock-based Compensation Cost
Stock-based compensation expense	$ 6,824	$ 2,288	$ 9,542	$ 5,607

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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Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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