XML 73 R35.htm IDEA: XBRL DOCUMENT v3.21.1
Balance Sheet Details - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]    
Long-term investments $ 12,199,000 $ 0
Depreciation expense $ 217,000 $ 83,000