Quarterly report pursuant to Section 13 or 15(d)

Nature of Business and Basis of Presentation - Additional Information (Detail)

v3.10.0.1
Nature of Business and Basis of Presentation - Additional Information (Detail)
$ in Thousands
3 Months Ended 9 Months Ended
May 23, 2018
Aug. 01, 2017
Jan. 05, 2017
Sep. 30, 2018
USD ($)
Sep. 30, 2017
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2017
USD ($)
Dec. 31, 2017
USD ($)
Nature Of Business And Basis Of Presentation [Line Items]                
Reverse stock split ratio 0.1              
Accumulated deficit       $ (21,744)   $ (21,744)   $ (12,694)
Net loss       (3,240) $ (6,472) (9,050) $ (6,843)  
Cash, cash equivalents and short term investments       13,200   13,200    
Working capital       $ 10,600   $ 10,600    
OncoGenex Pharmaceuticals, Inc [Member]                
Nature Of Business And Basis Of Presentation [Line Items]                
Reverse stock split ratio   0.0909 0.0909