Collaboration and License Agreements - Schedule of Financial Information Related to Collaboration and License Agreements (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	$ 3,656	$ 4,484
Deferred Revenue, Current	26,565	27,603
Deferred Revenue, Net of Current	50,886	53,617
Deferred Revenue, Total	77,451	81,220
Roche Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	750	750
Deferred Revenue, Current	9,390	11,238
Deferred Revenue, Net of Current	27,396	26,991
Deferred Revenue, Total	36,786	38,229
Biogen Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	155	776
Deferred Revenue, Current	14,775	13,965
Deferred Revenue, Net of Current	23,490	26,026
Deferred Revenue, Total	38,265	39,991
Calico Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Accounts Receivable	2,751	2,958
Deferred Revenue, Current	2,400	2,400
Deferred Revenue, Net of Current		600
Deferred Revenue, Total	$ 2,400	$ 3,000