Quarterly report pursuant to Section 13 or 15(d)

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

v3.8.0.1
Nature of Business and Basis of Presentation - Additional Information (Detail)
$ in Thousands
3 Months Ended
Aug. 01, 2017
Jan. 05, 2017
shares
Mar. 31, 2018
USD ($)
Mar. 31, 2017
USD ($)
Dec. 31, 2017
USD ($)
Nature Of Business And Basis Of Presentation [Line Items]          
Accumulated deficit     $ (15,716)   $ (12,694)
Net loss     (3,022) $ (205)  
Cash and cash equivalents at carrying value     4,165   $ 5,284
Working capital     $ 2,200    
OncoGenex Pharmaceuticals, Inc [Member]          
Nature Of Business And Basis Of Presentation [Line Items]          
Conversion of each issued share of Achieve common stock , shares converted | shares   8,210,118      
Reverse stock split ratio 0.0909 0.0909