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Balance Sheet Components - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]      
Depreciation and amortization expense $ 7,400,000 $ 4,600,000 $ 1,000,000.0
Disposal of property, plant, and equipment $ 0 $ 200,000 $ 0