| Stock-based Compensation - RSU Activity (Details) - RSU shares in Thousands | 6 Months Ended | 
|---|---|
| Jun. 30, 2020  $ / shares  shares | |
| Number of Shares | |
| Beginning Balance (in shares) | shares | 89 | 
| Granted (in shares) | shares | 98 | 
| Vested (in shares) | shares | (12) | 
| Forfeited (in shares) | shares | (28) | 
| Ending Balance (in shares) | shares | 147 | 
| Weighted- Average Grant Date Fair Value | |
| Beginning Balance (in dollars per share) | $ / shares | $ 10.77 | 
| Granted (in dollars per share) | $ / shares | 3.43 | 
| Vested (in dollars per share) | $ / shares | 5.74 | 
| Forfeited (in dollars per share) | $ / shares | 11.03 | 
| Ending Balance (in dollars per share) | $ / shares | $ 6.20 | 
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available. 
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available. 
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- Definition Gross number of share options (or share units) granted during the period. No definition available. 
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Number of non-vested options outstanding. No definition available. 
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- Definition Number of non-vested options forfeited. No definition available. 
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- Definition Weighted average grant-date fair value of non-vested options forfeited. No definition available. 
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- Definition Weighted average grant-date fair value of non-vested options outstanding. No definition available. 
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- Definition Number of options vested. No definition available. 
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- Definition Weighted average grant-date fair value of options vested. No definition available. 
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- Details 
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