Collaboration and License Agreements - Takeda Pharmaceutical Company Limited (Details)		3 Months Ended
	Oct. 07, 2020 USD ($) bundle obligation	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2022 USD ($)	Jan. 31, 2021 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Development regulatory and sales milestones payments		$ 4,100,000,000
Revenues		62,546,000	$ 27,439,000
Deferred revenue, net of current portion		40,789,000		$ 55,950,000
Deferred revenue		66,281,000		$ 74,099,000
Takeda License Agreement | License and Co-Funding Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Cash received as due under collaboration agreement					$ 300,000,000
Number of distinct bundle | bundle	1
Number of distinct performance obligations | obligation	1
Initial transaction price	$ 300,000,000
Revenues		16,300,000	$ 20,800,000
Contract assets		0
Takeda License Agreement | License and Co-Funding Agreement | Deferred Revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue, net of current portion		107,100,000
Deferred revenue		66,300,000
Takeda License Agreement | License and Co-Funding Agreement | Accrued Expenses
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue		$ 9,800,000
Takeda License Agreement | License and Co-Funding Agreement | Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of eligible to receive tiered royalties on net sales	20.00%
Takeda License Agreement | License and Co-Funding Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of eligible to receive tiered royalties on net sales	25.00%
Development regulatory and sales milestones payments					$ 595,000,000