Summary of Aggregate Non-Cancelable Contractual Obligations Arising from Manufacturing Obligations (Detail) - Manufacturing Commitments Agreement [Member] - Catalent and Thermo [Member] $ in Thousands	Mar. 31, 2020 USD ($)
Commitments And Contingencies [Line Items]
2020 (April - December)	$ 334,096
2021	192,121
2022	62,409
2023	58,553
2024	58,309
Thereafter	149,350
Total manufacturing commitments	$ 854,838	[1]

[1] Total manufacturing commitments include both Catalent and Thermo Agreements. Related to the embedded lease for the two clean room suites at Catalent that have commenced as of March 31, 2020, the Company recorded an ROU asset and a lease liability. Please see Note 13. Leases for further details.