Stock-based Awards (Details 3 - Stock comp by FSLI) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Stock-based Compensation Cost
Stock-based compensation expense	$ 8,972	$ 6,846	$ 18,069	$ 12,753
Amount capitalized to internal software use	473	332	807	550
Total stock-based compensation cost	9,445	7,178	18,876	13,303
Cost of revenue
Stock-based Compensation Cost
Stock-based compensation expense	443	233	741	436
Sales and marketing
Stock-based Compensation Cost
Stock-based compensation expense	3,543	2,160	6,670	3,905
Technology and development
Stock-based Compensation Cost
Stock-based compensation expense	2,698	1,600	5,051	2,898
General and administrative
Stock-based Compensation Cost
Stock-based compensation expense	$ 2,288	$ 2,853	$ 5,607	$ 5,514

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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