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Number of performance obligations.

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Payment receivable for license agreement reimbursement of previously costs incurred.

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Upfront cash payment received.

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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.

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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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License, Collaboration and Other Significant Agreements - International Collaboration and License Agreement with Otsuka Pharmaceutical Co. Ltd. Narrative (Details) $ in Thousands	12 Months Ended			69 Months Ended
	Dec. 31, 2022 USD ($) performance_obligation	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2022 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	$ 292,484	$ 211,650	$ 294,644
Deferred revenue	47,034			$ 47,034
Accounts payable
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue	0	3,171	7,227	0
Prepaid expenses and other current assets
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accounts receivable	781	4,309	1,722	781
License, collaboration and other revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	$ 115,535	71,362	166,406
Otsuka Pharmaceutical Co. Ltd. \| Otsuka International Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of performance obligations \| performance_obligation	3
Reimbursement for counterparty share of costs previously incurred	$ 200
Estimate subsequent cost share payment receivable				$ 216,700
Otsuka Pharmaceutical Co. Ltd. \| Otsuka International Agreement \| Accounts payable
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue		900
Otsuka Pharmaceutical Co. Ltd. \| Otsuka International Agreement \| Prepaid expenses and other current assets
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accounts receivable		1,300
Otsuka Pharmaceutical Co. Ltd. \| Otsuka International Agreement \| License, collaboration and other revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total revenues	5,503	$ 16,449	$ 45,451
Otsuka Pharmaceutical Co. Ltd. \| Up-front, Non-refundable and Non-creditable \| Otsuka International Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront cash payment received	$ 73,000