Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Schedule of Weighted-Average Assumptions Used for Calculating Value of Options Granted (Detail)

v3.3.1.900
Summary of Significant Accounting Policies - Schedule of Weighted-Average Assumptions Used for Calculating Value of Options Granted (Detail)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]    
Risk free interest rate 1.47%  
Risk free interest rate 1.89%  
Risk free interest rate   1.77%
Dividend yield 0.00% 0.00%
Expected volatility 72.65%  
Expected volatility 75.07%  
Expected volatility   74.66%
Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]    
Expected term 5 years 5 years 7 months 6 days
Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]    
Expected term 6 years 1 month 6 days 5 years 9 months 18 days