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Balance Sheet Components - Additional Information (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]      
Depreciation expense $ 400 $ 300 $ 200
Payments received in advance of shipments 735 $ 1,371  
Company recognized revenue $ 1,400