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Supplemental Financial Statement Information - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]        
Depreciation and amortization expense $ 328,000 $ 399,000 $ 687,000 $ 826,000
Contractual settlement of upside payment received $ 2,500,000