Collaboration Revenue - Changes in Contract Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue - related party, Deductions	$ (6,634)	$ (6,615)
ASU 2014-09 [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue - related party, Balance at beginning of period	110,071	137,259
Deferred revenue - related party, Deductions	(5,462)	(6,615)
Deferred revenue - related party, Balance at end of period	104,609	130,644
Deferred revenue, Balance at beginning of period	9,668
Deferred revenue, Additions	816	6,667
Deferred revenue, Deductions	(1,988)	(260)
Deferred revenue, Balance at end of period	$ 8,496	$ 6,407