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
Income Tax Disclosure [Line Items]      
Deferred Tax Assets, Valuation Allowance $ 41,142 $ 26,201  
Effective Income Tax Rate Reconciliation Prior Year State Net Operating Loss True Up   2.00% 1.00%
Effective Income Tax Rate Reconciliation Prior Year Federal Net Operating Loss True Up 1.00% 3.00%  
Effective Income Tax Rate Reconciliation State Rate Change     3.00%
Error Related To Taxation Overstatement Of Gross Deferred Tax Asset Amount   3,600,000  
Error Related To Taxation Understatement Of Valuation Amount   3,600,000  
Tax Payer Relief Act Research Credit Extension Period   2 years  
Unrecognized Tax Benefits, Beginning Balance 329,000    
Orphan Drug Tax Credit [Member]
      
Income Tax Disclosure [Line Items]      
Tax Credit Carryforward, Amount 1,300,000    
Research Tax Credit Carryforward [Member]
      
Income Tax Disclosure [Line Items]      
Tax Credit Carryforward, Amount 2,700,000    
Domestic Tax Authority [Member]
      
Income Tax Disclosure [Line Items]      
Operating Loss Carryforwards 87,600,000    
Domestic Tax Authority [Member] | Additional Paid-in Capital [Member]
      
Income Tax Disclosure [Line Items]      
Operating Loss Carryforwards 2,700,000    
State and Local Jurisdiction [Member]
      
Income Tax Disclosure [Line Items]      
Operating Loss Carryforwards 35,200,000    
State and Local Jurisdiction [Member] | Additional Paid-in Capital [Member]
      
Income Tax Disclosure [Line Items]      
Operating Loss Carryforwards $ 1,500,000