Annual report pursuant to Section 13 and 15(d)

Share-based Compensation - Summary of Stock Option and Inducement Stock Option Activity (Detail)

v3.3.1.900
Share-based Compensation - Summary of Stock Option and Inducement Stock Option Activity (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
2007 Plan (Options) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Authorized Shares, Options outstanding, beginning balance 595,000 1,593,334  
Weighted-Average Remaining Contractual Term (in Years), Granted 0 years 1 year 4 months 21 days  
Weighted-Average Remaining Contractual Term (in Years) 4 months 28 days 1 year 6 months 4 days 3 years 1 month 2 days
Number of Authorized Shares, Granted   245,000  
Number of Authorized Shares, Exercised (52,030) (212,949)  
Number of Authorized Shares, Exercised shares forgone to satisfy minimum statutory withholding (7,688) (38,029)  
Number of Authorized Shares, Cashless exercise (41,950)    
Number of Authorized Shares, Forfeited (5,000) (992,356)  
Number of Authorized Shares, Options outstanding, ending balance 488,332 595,000 1,593,334
Number of Authorized Shares, Exercisable 416,667    
Weighted-Average Exercise Price, Outstanding, beginning balance $ 2.19 $ 2.11  
Weighted-Average Exercise Price, Granted   2.83  
Weighted-Average Exercise Price, Exercised 1.64 2.59  
Weighted-Average Exercise Price, Exercised shares forgone to satisfy minimum statutory withholding 1.76 2.00  
Cashless exercise 1.70    
Weighted-Average Exercise Price, Forfeited 1.93 2.23  
Weighted-Average Exercise Price, Outstanding, ending balance $ 2.31 $ 2.19 $ 2.11
Aggregate Intrinsic value, Outstanding, beginning balance $ 571,717 $ 53,083  
Weighted-Average Exercise Price, Exercisable $ 2.33    
Aggregate Intrinsic value, Exercised $ 140,368 803,234  
Aggregate Intrinsic value, Outstanding, ending balance $ 348,415 $ 571,717 $ 53,083
2014 Plan (Options) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Authorized Shares, Options outstanding, beginning balance 530,000    
Weighted-Average Remaining Contractual Term (in Years), Granted 3 years 3 months 5 years  
Weighted-Average Remaining Contractual Term (in Years) 3 years 6 months 29 days 5 years  
Number of Authorized Shares, Granted 470,000 530,000  
Number of Authorized Shares, Forfeited (30,000)    
Number of Authorized Shares, Options outstanding, ending balance 970,000 530,000  
Number of Authorized Shares, Exercisable 410,903    
Weighted-Average Exercise Price, Outstanding, beginning balance $ 2.69    
Weighted-Average Exercise Price, Granted 2.90 $ 2.69  
Weighted-Average Exercise Price, Forfeited 2.69    
Weighted-Average Exercise Price, Outstanding, ending balance $ 2.79 $ 2.69  
Aggregate Intrinsic value, Outstanding, beginning balance $ 243,800    
Weighted-Average Exercise Price, Exercisable $ 2.85    
Aggregate Intrinsic value, Outstanding, ending balance $ 222,200 $ 243,800  
Inducement Stock Options [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Authorized Shares, Options outstanding, beginning balance 800,000 800,000  
Weighted-Average Remaining Contractual Term (in Years) 2 years 10 months 24 days 3 years 10 months 21 days 4 years 10 months 13 days
Number of Authorized Shares, Options outstanding, ending balance 800,000 800,000 800,000
Number of Authorized Shares, Exercisable 547,916    
Weighted-Average Exercise Price, Outstanding, beginning balance $ 2.25 $ 2.25  
Weighted-Average Exercise Price, Outstanding, ending balance $ 2.25 $ 2.25 $ 2.25
Aggregate Intrinsic value, Outstanding, beginning balance $ 720,000 $ 156,000  
Weighted-Average Exercise Price, Exercisable $ 2.25    
Aggregate Intrinsic value, Outstanding, ending balance $ 616,000 $ 720,000 $ 156,000