Income Taxes (Details 2) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Income Tax [Line Items]    
Valuation allowance $ 42,055,000 $ 38,406,000
Change in valuation 10,485,000 3,649,000
Valuation allowance 39,559,000 42,055,000
Establisment and reversal in 2014 - Convertible Bridge notes [Member]    
Income Tax [Line Items]    
Valuation allowance   897,000
Establishment in 2014 - Deerfield note [Member]    
Income Tax [Line Items]    
Valuation allowance   $ (13,878,000)