Share-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based compensation expense:
Share-based compensation costs	$ 1,796	$ 964	$ 4,366	$ 2,920
Amount capitalized to internal use software	0	1	1	2
Total share-based compensation costs	1,796	963	4,365	2,918
Cost of revenues [Member]
Share-based compensation expense:
Share-based compensation costs	2	20	21	59
Sales and marketing [Member]
Share-based compensation expense:
Share-based compensation costs	520	409	904	1,222
Technology support [Member]
Share-based compensation expense:
Share-based compensation costs	886	138	1,213	401
General and administrative [Member]
Share-based compensation expense:
Share-based compensation costs	$ 388	$ 397	$ 2,228	$ 1,238

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

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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