Annual report pursuant to Section 13 and 15(d)

Selected Quarterly Financial Data (Unaudited) - Summary of Quarterly Financial Data (Detail)

v3.10.0.1
Selected Quarterly Financial Data (Unaudited) - Summary of Quarterly Financial Data (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]                      
Collaboration revenue         $ 5,207     $ 4,793   $ 10,000  
Type of Revenue [Extensible List] us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember us-gaap:LicenseAndServiceMember
Total operating expenses $ 20,555 $ 21,129 $ 17,971 $ 12,850 $ 9,563 $ 6,394 $ 7,626 $ 7,742 $ 72,505 $ 31,325 $ 25,586
Net loss $ (19,449) $ (18,563) $ (17,531) $ (17,005) $ (5,043) $ (8,234) $ (8,929) $ (5,351) $ (72,548) $ (27,557) $ (26,671)
Basic net loss per common share $ (0.32) $ (0.31) $ (0.30) $ (0.32) $ (0.11) $ (0.21) $ (0.31) $ (0.20) $ (1.25) $ (0.79) $ (1.14)
Diluted net loss per common share $ (0.32) $ (0.34) $ (0.30) $ (0.32) $ (0.11) $ (0.21) $ (0.31) $ (0.20) $ (1.26) $ (0.79) $ (1.14)