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Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Current assets: |  |
Cash equivalents | $ 31,676 | $ 13,359
Short-term investments | 61,615 | 20,086
Assets measured at fair value | 93,291 | 33,445
Current liabilities: |  |
Liabilities measured at fair value |  | 2,158
Money Market Funds |  |
Current assets: |  |
Cash equivalents | 15,677 | 12,859
Corporate Debt Securities |  |
Current assets: |  |
Cash equivalents | 2,500 | 500
Short-term investments | 11,588 | 11,349
Commercial Paper |  |
Current assets: |  |
Cash equivalents | 13,499 |
Short-term investments | 50,027 | 5,987
Government Agency Bonds |  |
Current assets: |  |
Short-term investments |  | 2,750
Preferred Stock Tranche Obligation |  |
Current liabilities: |  |
Liabilities measured at fair value |  | 2,158
Level 1 |  |
Current assets: |  |
Cash equivalents | 15,677 | 12,859
Assets measured at fair value | 15,677 | 12,859
Level 1 | Money Market Funds |  |
Current assets: |  |
Cash equivalents | 15,677 | 12,859
Level 2 |  |
Current assets: |  |
Cash equivalents | 15,999 | 500
Short-term investments | 61,615 | 20,086
Assets measured at fair value | 77,614 | 20,586
Level 2 | Corporate Debt Securities |  |
Current assets: |  |
Cash equivalents | 2,500 | 500
Short-term investments | 11,588 | 11,349
Level 2 | Commercial Paper |  |
Current assets: |  |
Cash equivalents | 13,499 |
Short-term investments | $ 50,027 | 5,987
Level 2 | Government Agency Bonds |  |
Current assets: |  |
Short-term investments |  | 2,750
Level 3 |  |
Current liabilities: |  |
Liabilities measured at fair value |  | 2,158
Level 3 | Preferred Stock Tranche Obligation |  |
Current liabilities: |  |
Liabilities measured at fair value |  | $ 2,158

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