Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Summary of Fair Value of Warrants Issued (Detail)

v2.4.0.8
Common Stock - Summary of Fair Value of Warrants Issued (Detail) (Stock warrants [Member])
6 Months Ended
Jun. 30, 2014
Jun. 30, 2013
Stock warrants [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rates 0.22% 0.45%
Expected dividend yield 0.00% 0.00%
Expected life 1 year 3 months 18 days 2 years 3 months 18 days
Expected volatility 93.00% 44.00%