Share-based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 1,553	$ 1,057
Cost of net revenues
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	228	123
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	292	175
Sales and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	463	214
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation expense	570	$ 545
Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized expense	$ 11,700
Recognition period	2 years 10 months 13 days
RSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized expense	$ 700
Recognition period	1 year 3 months 29 days

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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