Quarterly report pursuant to Section 13 or 15(d)

Public Offering - Additional Information (Detail)

v3.5.0.2
Public Offering - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 3 Months Ended 9 Months Ended
Jul. 24, 2015
Jul. 31, 2015
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Initial Public Offering And Issuance Of Senior Unsecured Notes [Line Items]            
Number of shares, Options exercised     0 0 0 0
Gross proceeds from issuance initial public offering   $ 28.3        
Net proceeds from issuance initial public offering   $ 25.8        
IPO [Member]            
Initial Public Offering And Issuance Of Senior Unsecured Notes [Line Items]            
Common stock, shares issued   9,090,909        
Sales of common stock, price per share   $ 2.75        
Over-Allotment Option [Member]            
Initial Public Offering And Issuance Of Senior Unsecured Notes [Line Items]            
Sales of common stock, price per share $ 2.75          
Number of shares, Options exercised 1,211,827