Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Additional Information (Detail)

v3.10.0.1
Stockholders' Equity - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2013
Jul. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Warrants exercisable, outstanding 13,000   13,000      
Stock-based compensation $ 900 $ 800 $ 1,912 $ 2,063    
2013 Warrants [Member] | Convertible promissory notes [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Warrant expiration date         May 30, 2018  
2013 Warrants [Member] | Series B Preferred Stock [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Warrant exercisable to purchase shares         1,124,026  
2013 Warrants [Member] | Series B Preferred Stock [Member] | Convertible promissory notes [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Exercise price of warrant per share         $ 0.90  
Lender Warrants [Member] | Series B convertible preferred stock [Member] | Term Loan One [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Exercise price of warrant per share         $ 0.90  
Warrant issued         111,112  
Warrant expiration date         Jul. 03, 2023  
Common Stock [Member] | 2013 Warrants [Member] | Convertible promissory notes [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Exercise price of warrant per share           $ 7.43
Common Stock [Member] | 2013 Warrants [Member] | Convertible promissory notes [Member] | Post IPO [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Warrants exercisable, outstanding           136,236
Common Stock [Member] | Lender Warrants [Member] | Convertible promissory notes [Member]            
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]            
Exercise price of warrant per share           $ 7.43
Warrants exercisable, outstanding           13,468