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Commitments and Contingencies - Additional Information (Detail) - Office Space and Research Facilities Lease - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Commitment And Contingencies [Line Items]        
Operating leases, rent expense $ 301,000 $ 255,000 $ 548,000 $ 490,000
Operating lease, renewal term 5 years   5 years  
Lease expiration date     2025-11