Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Additional Information (Detail)

v3.7.0.1
Common Stock - Additional Information (Detail) - 2012 Equity Incentive Plan [Member] - Restricted Stock [Member] - USD ($)
3 Months Ended
Feb. 09, 2017
Feb. 15, 2016
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Class of Stock [Line Items]                    
Unrecognized compensation expense           $ 69,685        
Non-employee Directors [Member]                    
Class of Stock [Line Items]                    
Restricted shares awarded to each non-employee director 40,000 40,000                
Restricted shares vest in each quarter end           10,000 10,000 10,000 10,000 10,000
Non-employee Directors [Member] | Scenario, Forecast [Member]                    
Class of Stock [Line Items]                    
Restricted shares vest in each quarter end     10,000 10,000 10,000