Balance Sheets Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid Expense And Other Assets Current [Abstract]
Advance to suppliers	$ 0	$ 853
Prepaid expenses	2,398	1,074
Other current assets	2,078	722
Total prepaid and other current assets	$ 4,476	$ 2,649