XML 48 R35.htm IDEA: XBRL DOCUMENT v3.19.3
Collaboration Agreements - Deferred Revenue - Additional Information (Detail) - USD ($)
$ in Thousands
Sep. 30, 2019
Dec. 31, 2018
Contract with Customer, Liability [Abstract]    
Deferred revenue $ 53,988 $ 0
AstraZeneca Agreements [Member] | China [Member]    
Contract with Customer, Liability [Abstract]    
Deferred revenue $ 700