Quarterly report pursuant to Section 13 or 15(d)

Merger with Private Molecular - Additional Information (Detail)

v3.8.0.1
Merger with Private Molecular - Additional Information (Detail) - USD ($)
3 Months Ended
Aug. 01, 2017
Mar. 31, 2018
Mar. 31, 2017
Jun. 01, 2017
Mar. 24, 2017
Business Acquisition [Line Items]          
Exercise price per share on stock options after reverse stock split   $ 10.69      
Stock compensation   $ 643,000 $ 26,000    
2014 Equity Incentive Plan          
Business Acquisition [Line Items]          
Stock compensation   $ 1,200,000      
Threshold          
Business Acquisition [Line Items]          
Common stock shares issued in exchange of each share 7.7844        
Threshold equity holders ownership interest 34.40%        
Private Molecular equity holders ownership interest 65.60%        
Stock option outstanding to purchase common stock 963,681        
Number of vested stock option shares after reverse stock split 963,681        
Exercise price per share on stock options after reverse stock split $ 33.62        
Fair value inputs discount rate 12.00%        
Transaction costs associated with Merger $ 2,000,000        
Principal amount       $ 2,000,000 $ 2,000,000
Promissory note interest rate         1.00%