Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Detail)

v2.4.0.8
Income Taxes - Additional Information (Detail) (USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Components Of Income Before Taxes [Line Items]      
Income tax provision $ 202,000      
NOL DTA related to excess benefits from stock option exercises 400,000    
Increase in valuation allowance 11,600,000 7,800,000 11,600,000
Accrued interest or penalties 0 0  
Federal [Member]
     
Components Of Income Before Taxes [Line Items]      
Federal and State net operating loss carryforwards 81,000,000    
Year net operating loss carryforwards begin to expire 2021    
Research and development credits 3,200,000    
Year research and development credits begin to expire 2022    
State [Member]
     
Components Of Income Before Taxes [Line Items]      
Federal and State net operating loss carryforwards 78,000,000    
Year net operating loss carryforwards begin to expire 2015    
Research and development credits $ 4,300,000