Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Schedule of Weighted-Average Assumptions Used for Calculating Value of Options Granted (Detail)

v3.7.0.1
Stock-Based Compensation - Schedule of Weighted-Average Assumptions Used for Calculating Value of Options Granted (Detail)
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]    
Risk free interest rate 2.04% 1.35%
Risk free interest rate 2.16% 1.61%
Dividend yield 0.00% 0.00%
Expected volatility 75.09% 75.53%
Expected volatility 75.13% 76.00%
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
Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]    
Expected term 5 years 8 months 12 days 5 years 8 months 12 days