Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation - Additional Information (Detail)

v3.10.0.1
Basis of Presentation - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]          
Revenues     $ 0    
Net loss $ 2,757,835 $ 2,067,230 7,158,521 $ 5,270,792  
Cash used in operations     6,101,876 $ 5,005,050  
Accumulated deficit $ 108,617,988   $ 108,617,988   $ 101,400,797