Annual report pursuant to Section 13 and 15(d)

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

v3.6.0.2
Share-based Compensation - Summary of Stock Option and Inducement Stock Option Activity (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
2007 Plan (Options) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Authorized Shares, Options outstanding, beginning balance 488,332 595,000  
Number of Authorized Shares, Exercised   (52,030)  
Number of Authorized Shares, Exercised shares forgone to satisfy minimum statutory withholding   (7,688)  
Number of Authorized Shares, Cashless exercise   (41,950)  
Number of Authorized Shares, Forfeited   (5,000)  
Number of Authorized Shares, Options outstanding, ending balance 488,332 488,332 595,000
Weighted-Average Exercise Price, Outstanding, beginning balance $ 2.31 $ 2.19  
Number of Authorized Shares, Exercisable 483,332    
Weighted-Average Exercise Price, Exercised   1.64  
Weighted-Average Exercise Price, Exercised shares forgone to satisfy minimum statutory withholding   1.76  
Cashless exercise   1.70  
Weighted-Average Exercise Price, Forfeited   1.93  
Weighted-Average Exercise Price, Outstanding, ending balance $ 2.31 $ 2.31 $ 2.19
Aggregate Intrinsic value, Outstanding, beginning balance $ 348,415 $ 571,717  
Weighted-Average Exercise Price, Exercisable $ 2.29    
Aggregate Intrinsic value, Exercised   $ 140,368  
Weighted-Average Remaining Contractual Term (in Years), Granted 0 years 0 years  
Aggregate Intrinsic value, Outstanding, ending balance $ 118,899 $ 348,415 $ 571,717
Weighted-Average Remaining Contractual Term (in Years) 3 months 4 months 28 days 1 year 6 months 4 days
2014 Plan (Options) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Authorized Shares, Options outstanding, beginning balance 970,000 530,000  
Number of Authorized Shares, Granted 600,000 470,000  
Number of Authorized Shares, Exercised (1,866)    
Number of Authorized Shares, Exercised shares forgone to satisfy minimum statutory withholding (798)    
Number of Authorized Shares, Cashless exercise (12,614)    
Number of Authorized Shares, Forfeited (304,723) (30,000)  
Number of Authorized Shares, Options outstanding, ending balance 1,249,999 970,000 530,000
Weighted-Average Exercise Price, Outstanding, beginning balance $ 2.79 $ 2.69  
Number of Authorized Shares, Exercisable 616,597 410,903  
Weighted-Average Exercise Price, Granted $ 2.76 $ 2.90  
Weighted-Average Exercise Price, Exercised 2.69    
Weighted-Average Exercise Price, Exercised shares forgone to satisfy minimum statutory withholding 2.69    
Cashless exercise 2.69    
Weighted-Average Exercise Price, Forfeited 2.70 2.69  
Weighted-Average Exercise Price, Outstanding, ending balance $ 2.80 $ 2.79 $ 2.69
Aggregate Intrinsic value, Outstanding, beginning balance $ 222,200 $ 243,800  
Weighted-Average Exercise Price, Exercisable $ 2.87 $ 2.85  
Weighted-Average Remaining Contractual Term (in Years), Granted 4 years 7 months 6 days 3 years 3 months  
Aggregate Intrinsic value, Outstanding, ending balance   $ 222,200 $ 243,800
Weighted-Average Remaining Contractual Term (in Years) 4 years 3 months 4 days 3 years 6 months 29 days 5 years
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  
Number of Authorized Shares, Options outstanding, ending balance 800,000 800,000 800,000
Weighted-Average Exercise Price, Outstanding, beginning balance $ 2.25 $ 2.25  
Number of Authorized Shares, Exercisable 756,250    
Weighted-Average Exercise Price, Outstanding, ending balance $ 2.25 $ 2.25 $ 2.25
Aggregate Intrinsic value, Outstanding, beginning balance $ 616,000 $ 720,000  
Weighted-Average Exercise Price, Exercisable $ 2.25    
Aggregate Intrinsic value, Outstanding, ending balance $ 240,000 $ 616,000 $ 720,000
Weighted-Average Remaining Contractual Term (in Years) 2 years 3 months 4 days 2 years 10 months 24 days 3 years 10 months 21 days