Stock-Based Compensation - Compensation expense (Details) - USD ($) $ in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2019  | 
Dec. 31, 2018  | 
Dec. 31, 2017  | 
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| Stock Based Compensation | |||
| Stock-based compensation | $ 10,511 | $ 5,707 | $ 5,292 | 
| Operating expense | |||
| Stock Based Compensation | |||
| Stock-based compensation | 113 | 108 | 178 | 
| Selling, general and administrative | |||
| Stock Based Compensation | |||
| Stock-based compensation | $ 10,398 | $ 5,599 | $ 5,114 | 
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Details 
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- Details 
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