Stock-based Compensation - Expense for Stock-Based Awards (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Compensation expense recognized
Stock-based compensation expense	$ 427	$ 1,256
Total unrecognized compensation costs related to unvested awards	$ 1,100
Weighted-average period of recognition for unrecognized compensation costs related to unvested awards	1 year 10 months 24 days
Selling and marketing
Compensation expense recognized
Stock-based compensation expense		77
General and Administrative
Compensation expense recognized
Stock-based compensation expense	$ 427	1,146
Research and development
Compensation expense recognized
Stock-based compensation expense		$ 33

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

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