Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Product revenue related reserves	$ 46,721	$ 45,249
Accrued contract manufacturing costs	26,098	27,622
Accrued clinical and pre-clinical costs	20,292	18,010
Accrued employee compensation costs	18,993	43,240
Accrued professional fees	11,219	10,707
Accrued milestone expense	8,893	18,390
Accrued royalties	6,400	6,301
Accrued property and equipment	5,887	1,181
Accrued collaboration cost sharing	4,821	9,000
Accrued interest expense	3,183	1,045
Other	8,214	4,782
Total accrued expenses	176,298	$ 185,527
Roche
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accrued Roche transaction costs	$ 15,577