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Development regulatory and sales milestones payments.

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Initial transaction price.

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Number of distinct bundle.

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Number of distinct performance obligations.

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Percentage of eligible to receive tiered royalties on net sales.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Collaboration and License Agreements - Takeda Pharmaceutical Company Limited (Details) $ in Thousands		12 Months Ended
	Oct. 07, 2020 USD ($) bundle obligation	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jan. 31, 2021 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues		$ 243,231	$ 138,287	$ 87,992
Deferred revenue, net of current portion		55,950	131,495
Deferred revenue		74,099	111,055
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
Number of distinct bundle \| bundle	1
Number of distinct performance obligations \| obligation	1
Initial transaction price	$ 300,000
Revenues		85,800	$ 90,800
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		123,400
Deferred revenue		67,400
Takeda License Agreement \| License and Co-Funding Agreement \| Accrued Expenses
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue		$ 8,600
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