v2.4.0.6
Summary of Option Activity under Plan and Related Information (Detail) (USD $)
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Shares    
Outstanding at end of period 3,298,297 1,547,122
Stock Options and Warrants
   
Shares    
Outstanding at beginning of period 2,135,630 1,236,342
Forfeited (237,333) (19,220)
Granted 1,400,000 330,000
Outstanding at end of period 3,298,297 1,547,122
Expected to vest 1,476,200 402,698
Options exercisable 878,297 875,958
Weighted Average Exercise Price    
Outstanding at beginning of period $ 1.26 $ 2.47
Forfeited $ 1.61 $ 1.89
Granted $ 0.90 $ 0.40
Outstanding at end of period $ 1.08 $ 2.03
Expected to vest $ 0.78 $ 2.03
Options exercisable $ 1.91 $ 2.60
Weighted-average fair value of options granted during the period $ 0.77 $ 0.32