Commitments and Contingencies - Additional Information (Detail) - Novo License Agreement [Member] - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 28, 2007
Developmental And Regulatory Milestone Payment | Maximum [Member] | Other Indication [Member]
Commitments And Contingencies [Line Items]
Potential milestone payment				$ 115,000,000.0
Developmental And Regulatory Milestone Payment | Maximum [Member] | Type 1 Diabetes [Member]
Commitments And Contingencies [Line Items]
Potential milestone payment				9,000,000.0
Developmental And Regulatory Milestone Payment | Maximum [Member] | Type 2 Diabetes [Member]
Commitments And Contingencies [Line Items]
Potential milestone payment				50,500,000
Sales-based Milestones Payment [Member]
Commitments And Contingencies [Line Items]
Potential milestone payment				$ 75,000,000.0
Satisfaction of Milestone Payment [Member]
Commitments And Contingencies [Line Items]
Potential milestone payment	$ 2,000,000.0	$ 0	$ 0