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Property and Equipment, Net - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Property Plant And Equipment [Line Items]    
Depreciation expense $ 632,000 $ 194,000
Property and equipment, gross 8,426,000 6,442,000
Construction in Progress [Member]    
Property Plant And Equipment [Line Items]    
Property and equipment, gross $ 239,000 $ 1,014,000