Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation - Additional Information (Detail)

v3.8.0.1
Basis of Presentation - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]          
Revenues     $ 0    
Net loss $ 2,067,230 $ 1,963,007 5,270,792 $ 4,338,507  
Cash used in operations     5,005,050 $ 5,111,024  
Accumulated deficit $ 99,940,064   $ 99,940,064   $ 94,669,272