Fair Value of Financial Instruments - Fair Value of Financial Instruments by Balance Sheet Class (Details) (Recurring Basis, USD $)
Mar. 31, 2015
Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total assets at fair value: $ 190,846,333 $ 85,801,024
Quoted Prices in Active Markets for Identical Assets (Level 1)
   
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total assets at fair value: 190,846,333 85,801,024
Money Market Funds    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total assets at fair value: 190,846,333 85,801,024
Money Market Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total assets at fair value: $ 190,846,333 $ 85,801,024