Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies - Additional Information (Detail)

v3.19.1
Commitments and Contingencies - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Other Commitments [Line Items]    
Property and equipment, net $ 6,851,000 $ 1,952,000
Accumulated amortization 1,333,000 412,000
Facilities Operating Leases    
Other Commitments [Line Items]    
Operating lease expense 1,500,000 625,000,000
Laboratory Equipment    
Other Commitments [Line Items]    
Property and equipment, net 99,000 162,000
Accumulated amortization $ 108,000 $ 75,000