Quarterly report pursuant to Section 13 or 15(d)

Leases, Other Commitments, and Contingencies - Additional Information (Detail)

v3.19.2
Leases, Other Commitments, and Contingencies - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Other Commitments [Line Items]          
Total rent expense under operating lease $ 20,000 $ 78,000 $ 69,000 $ 160,000  
Forward purchase commitment amount     19,000,000    
Equipment [Member]          
Other Commitments [Line Items]          
Lease term         4 years
Restricted cash 1,500,000   $ 1,500,000    
Sale-leaseback draw down amount $ 200,000        
Maximum [Member] | Equipment [Member]          
Other Commitments [Line Items]          
Sale-leaseback that can be financed or leased         $ 900,000