Quarterly report pursuant to Section 13 or 15(d)

Investment at Fair Value - Additional Information (Detail)

v2.4.0.8
Investment at Fair Value - Additional Information (Detail) (USD $)
3 Months Ended
Mar. 31, 2014
Mar. 17, 2014
Investment [Line Items]    
Equity Method Investment Ownership Percentage 100.00%  
Argus Neurooptics LLC [Member]
   
Investment [Line Items]    
Equity Method Investments   $ 250,000
Equity Method Investment Ownership Percentage   35.00%
Percentage of Revenue Share Amount 5.00%  
Argus Neurooptics LLC [Member] | Class A Preferred Stock [Member]
   
Investment [Line Items]    
Shares Received Under Purchase Agreement 13,409,962  
Percentage of Shares Received Under Purchase Agreement 83.00%  
Shares Reserved Under Purchase Agreement $ 16,091,954