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Balance Sheet Components - Additional Information (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Property Plant And Equipment [Abstract]        
Depreciation $ 87,000 $ 57,000 $ 162,000 $ 117,000