Stock-Based Compensation - Amounts Recognized (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stock Options
Total stock-based compensation	$ 2,903	$ 1,389	$ 5,652	$ 2,780
Unearned stock-based compensation	33,900		$ 33,900
Weighted average recognition period			2 years 9 months 18 days
Cost of goods sold
Stock Options
Total stock-based compensation	33	26	$ 86	52
Research and development
Stock Options
Total stock-based compensation	372	161	717	324
Selling, general and administrative
Stock Options
Total stock-based compensation	$ 2,498	$ 1,202	$ 4,849	$ 2,404

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

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