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Balance Sheet Details - Additional Information (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]          
Short-term investments with unrealized losses         $ 0
Depreciation expense $ 26,000 $ 19,000 $ 51,000 $ 38,000